| proliferating spermatogonia are susceptible to reactive oxygen species attack in japanese eel (anguilla japonica). | oxidative stress has been implicated in pathogenesis of many diseases, but few studies describe its influence on spermatogenesis. in this study, we analyzed the direct influence of hypoxanthine (hx)-induced reactive oxygen species (ros) on spermatogenesis in fish using the japanese eel (anguilla japonica) testicular organ culture system. testicular fragments of eels were cultured in 0.1-100 μm hx with or without 10 ng/ml 11-ketotestosterone (11-kt). immunohistochemistry for 5-bromo-2-deoxyuridin ... | 2012 | 22786824 |
| withdrawn: molecular cloning and expression analysis of relaxin 3c in japanese eel, anguilla japonica. | this article has been withdrawn at the request of the author(s) and/or editor. the publisher apologizes for any inconvenience this may cause. the full elsevier policy on article withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy. | 2010 | 20233608 |
| sympatric spawning but allopatric distribution of anguilla japonica and anguilla marmorata: temperature- and oceanic current-dependent sieving. | anguilla japonica and anguilla marmorata share overlapping spawning sites, similar drifting routes, and comparable larval durations. however, they exhibit allopatric geographical distributions in east asia. to clarify this ecological discrepancy, glass eels from estuaries in taiwan, the philippines, indonesia, and china were collected monthly, and the survival rate of a. marmorata under varying water salinities and temperatures was examined. the composition ratio of these 2 eel species showed a ... | 2012 | 22675481 |
| taurine plays an important role in the protection of spermatogonia from oxidative stress. | it has been demonstrated that taurine has various physiological functions in the body. we demonstrated that taurine is abundant in the serum, liver, muscle and testis of the japanese eel (anguilla japonica). in the eel testis, taurine is found mainly in spermatogonia and is weakly expressed also in the sertoli cells. we have further found in the eel testis that taurine is actively accumulated via the sodium/chloride-dependent taurine transporter (taut; slc6a6), which is expressed in germ cells. ... | 2012 | 22619065 |
| purification and identification of two carnosine-cleaving enzymes, carnosine dipeptidase i and xaa-methyl-his dipeptidase, from japanese eel (anguilla japonica). | three enzymes, carnosine dipeptidase i (ec 3.4.13.20, cndp1), carnosine dipeptidase ii (ec 3.4.13.18, cndp2), and xaa-methyl-his dipeptidase (or anserinase: ec 3.4.13.5, ansn), are known to be capable of catalyzing the hydrolysis of carnosine (β-alanyl-l-histidine), in vertebrates. here we report the purification and identification of two unidentified carnosine-cleaving enzymes from japanese eel (anguilla japonica). two different dipeptidases were successfully purified to homogeneity from the sk ... | 2012 | 22525515 |
| re-evaluation of the optimum dietary vitamin c requirement in juvenile eel, anguilla japonica by using l-ascorbyl-2-monophosphate. | this study was conducted to re-evaluate the dietary vitamin c requirement in juvenile eel, anguilla japonica by using l-ascorbyl-2-monophosphate (amp) as the vitamin c source. five semi-purified experimental diets were formulated to contain 0 (amp0), 30 (amp24), 60 (amp52), 120 (amp108) and 1,200 (amp1137) mg amp kg-1 diet on a dry matter basis. casein and defatted fish meal were used as the main protein sources in the semi-purified experimental diets. after a 4-week conditioning period, fish in ... | 2012 | 25049484 |
| steroidogenic response of carp ovaries to piscine fsh and lh depends on the reproductive phase. | the gonadotropins (gths) follicle-stimulating hormone (fsh) and luteinizing hormone (lh) are the key regulators of reproduction. we determined the competence of heterologous recombinant gths at eliciting steroid secretion from carp ovaries at different reproductive stages. we collected carp ovaries at: early, mid and end vitellogenesis, when most of the oocytes still contained a germinal vesicle (gv) at a central stage, and mature ovaries with a migrating gv. plasma estradiol (e2) levels at earl ... | 2012 | 22522050 |
| 11-ketotestosterone synchronously induces oocyte development and silvering-related changes in the japanese eel, anguilla japonica. | to evaluate the effects of sex steroids on silvering in the japanese eel, anguilla japonica, the development of oocytes, eye size, digestive tract, and swim bladder were studied in relation to observations of the profiles of plasma levels of sex steroids (estradiol 17β, e2; testosterone, t; 11-ketotestosterone; 11-kt) during silvering for each sex and by administrating 11-kt to yellow eels. all steroids examined in the study increased in female eels after silvering had begun, whereas in males, o ... | 2012 | 22468835 |
| distribution of pepsinogen- and ghrelin-producing cells in the digestive tract of japanese eel (anguilla japonica) during metamorphosis and the adult stage. | pepsinogen is the precursor form of the gastric-specific digestive enzyme, pepsin. ghrelin is a representative gastric hormone with multiple functions in vertebrates, including the regulation of growth hormone release, stimulation of food intake and gastrointestinal motility function. we investigated chronological changes in the distribution of pepsinogen-expressing cells by in situ hybridization and ghrelin-immunoreactive cells by immunohistochemistry in the japanese eel (anguilla japonica) dur ... | 2011 | 21827762 |
| hatching enzyme of japanese eel anguilla japonica and the possible evolution of the egg envelope digestion mechanism. | we purified eel hatching enzyme (ehe) from the hatching liquid of japanese eel anguilla japonica belonging to elopomorpha to a single band on sds/page. tof-ms analysis revealed that the purified ehe contained several isozymes with similar molecular masses. comparison of the egg envelope digestion specificities of the purified ehe and of recombinant ehe4, one of the ehe isozymes, suggested that the isozymes contained in the purified ehe were functionally the same in terms of egg envelope digestio ... | 2011 | 21819542 |
| host size- and habitat-dependent intensity of heliconema longissimum (nematoda: physalopteridae) in the japanese eel (anguilla japonica). | heliconema longissimum (ortlepp, 1923) is an ecologically poorly known nematode found in the stomach of japanese eels, anguilla japonica temminck and schlegel. the occurrence of this nematode in japanese eels was surveyed in 2 contiguous brackish-water areas (misho cove and the lower renjoji river) of ehime prefecture, western japan, during april 2008 to march 2009. the factors associated with the nematode intensity were also assessed by applying generalized additive models (gam). heliconema lon ... | 2011 | 21671717 |
| expression and localization of aquaporin 1b during oocyte development in the japanese eel (anguilla japonica). | to elucidate the molecular mechanisms underling hydration during oocyte maturation, we characterized the structure of japanese eel (anguilla japonica) novel-water selective aquaporin 1 (aqp1b) that thought to be involved in oocyte hydration. the aqp1b cdna encodes a 263 amino acid protein that includes the six potential transmembrane domains and two asn-pro-ala motifs. reverse transcription-polymerase chain reaction showed transcription of japanese eel aqp1b in ovary and testis but not in the ot ... | 2011 | 21615964 |
| the mechanism for primordial germ-cell migration is conserved between japanese eel and zebrafish. | primordial germ cells (pgcs) are segregated and specified from somatic cells during early development. these cells arise elsewhere and have to migrate across the embryo to reach developing gonadal precursors. several molecules associated with pgc migration (i.e. dead-end, nanos1, and cxcr4) are highly conserved across phylum boundaries. however, since cell migration is a complicated process that is regulated spatially and temporally by multiple adaptors and signal effectors, the process is unlik ... | 2011 | 21931724 |
| localization of diversified relaxin gene transcripts in the brain of eels. | relaxin 3 (rln3) is a newly-discovered member of the insulin superfamily. we isolated three rln3-like cdnas from the brain of the japanese eel (anguilla japonica). the deduced amino acid sequences of the rln3-like cdnas contained the two-chain structure common to relaxin including a rxxxrxxi/v motif in the b-chain. phylogenetic analysis assigned the two prepropeptides into teleost/mammalian rln3 group, which are a pair of duplicates generated by the teleost-specific third-round whole genome dupl ... | 2011 | 21530530 |
| offshore spawning of conger myriaster in the western north pacific: evidence for convergent migration strategies of anguilliform eels in the atlantic and pacific. | the spawning area of the common japanese conger, conger myriaster, had remained unknown because spawning adults or its newly hatched larvae were never collected. using genetic identification, we determined that c. myriaster spawns far offshore in the western north pacific, just west of the spawning area of the japanese eel, anguilla japonica. in june 2008, six newly hatched c. myriaster larvae, 5.6-6.9 mm, were collected at the eastern edge of where many small unidentified conger leptocephali (7 ... | 2011 | 21509576 |
| modulation of ion transporter expression in gill mitochondrion-rich cells of eels acclimated to low-na(+) or-cl(-) freshwater. | in this study, we aimed to establish an experimental model to study the role of the gill mitochondrion-rich cells (mrcs) of freshwater fish in na(+) uptake and to examine the effect of adjusting external na(+) and cl(-) ions on selected ion transporters in gill mrcs. japanese eels (anguilla japonica) acclimated to deionized (di) water for 2 weeks were transferred directly to (a) ion-supplemented artificial freshwater (af), (b) na(+) -deficient af, or (c) cl(-) -deficient af for 2 days. the effec ... | 2011 | 21455947 |
| [seasonal changes of fish species composition and diversity in mudflat wetlands of hangzhou bay]. | in order to understand the spatiotemporal variation of fish species composition and biodiversity in the mudflat wetlands of hangzhou bay, thirty six surveys were conducted in the mudflat area, inning area, and aquaculture area in the south bank of the bay in. march (early spring), may (spring), july (summer), and october (autumn), 2009. a total of 41 species belonging to 9 orders and 16 families were observed, among which, cyprinid had the largest species number (14 species, 33.3% of the total), ... | 2010 | 21443016 |
| ovarian steroidogenesis and the role of sex steroid hormones on ovarian growth and maturation of the japanese eel. | three sex steroid hormones, estradiol-17β (e2), 11-ketotestosterone (11-kt), and 17α,20β-dihydroxy-4-pregnen-3-one (dhp), are well established as primary estrogen, androgen, and progestin, respectively, in teleost fish. japanese eel, anguilla japonica, would be a suitable candidate to study ovarian steroid physiology of fish because the ovarian growth and steroidogenesis is dormant under laboratory condition but can be induced by administration of exogenous gonadotropic reagents. in this review, ... | 2011 | 21414407 |
| dynamics of reproductive hormones during downstream migration in females of the japanese eel, anguilla japonica. | the profiles of sex steroids (estradiol-17β, testosterone and 11-ketotestosterone) and the mrna levels of gonadotropins (luteinizing hormone and follicle-stimulating hormone) were investigated before and after downstream migration in females of the japanese eel species anguilla japonica, which were collected in the brackish hamana lake and its inlet freshwater rivers. eels were separated into three groups using otolith microchemistry: 'migrants' that grew in the inlet rivers and then made a down ... | 2011 | 21385058 |
| androgens and very low density lipoprotein are essential for the growth of previtellogenic oocytes from japanese eel, anguilla japonica, in vitro. | to investigate the regulation of lipid uptake into the eel oocyte in more detail, effects of 11-ketotestosterone (11-kt) and lipid transporters (lipoproteins) were determined in vitro. ovarian explants from previtellogenic japanese eels (anguilla japonica) were incubated for 28 days with 11-kt and/or with very low density lipoproteins (vldl), low density lipoproteins (ldl), or high density lipoproteins (hdl) purified from eel plasma. the androgen 11-kt induced notable increases in oocyte diamete ... | 2011 | 21148104 |
| potent cardiovascular effects of homologous urotensin ii (uii)-related peptide and uii in unanesthetized eels after peripheral and central injections. | we cloned cdnas encoding urotensin ii (uii)-related peptide (urp) and uii in japanese eel, anguilla japonica, the former being the first such cloning in teleost fishes. unlike the exclusive expression of uii in the urophysis, the urp gene was expressed most abundantly in the brain (medulla oblongata) followed by the urophysis. peripheral injections of urp into eels increased blood pressure by 16.1 ± 0.8 mmhg at 0.1 nmol/kg in ventral aortic blood pressure (p(va)) and with similar potency and eff ... | 2011 | 21123764 |
| effects of extracellular environment factors on the motility in japanese eel spermatozoa. | we have examined the effects in vitro of the ionic composition, ph and temperature on the motility by the spermatozoa of the japanese eel (anguilla japonica). milt was obtained from 10 males that had been artificially matured by repeated injections of hcg. sperm motility was monitored with a vhs video recorder and a video camera connected to a microscope. the results showed that most of the sperm were highly motile in 250-700 mm nacl, 250-650 mm kcl and 350-550 mm cacl2 solution. the longest dur ... | 2011 | 20979577 |
| evolution of the teleostean zona pellucida gene inferred from the egg envelope protein genes of the japanese eel, anguilla japonica. | a fish egg envelope is composed of several glycoproteins, called zona pellucida (zp) proteins, which are conserved among vertebrate species. euteleost fishes synthesize zp proteins in the liver, while otocephalans synthesize them in the growing oocyte. we investigated zp proteins of the japanese eel, anguilla japonica, belonging to elopomorpha, which diverged earlier than euteleostei and otocephala. five major components of the egg envelope were purified and their partial amino acid sequences we ... | 2010 | 20977667 |
| modelling the growth of japanese eel anguilla japonica in the lower reach of the kao-ping river, southern taiwan: an information theory approach. | information theory was applied to select the best model fitting total length (l(t))-at-age data and calculate the averaged model for japanese eel anguilla japonica compiled from published literature and the differences in growth between sexes were examined. five candidate growth models were the von bertalanffy, generalized von bertalanffy, gompertz, logistic and power models. the von bertalanffy growth model with sex-specific coefficients was best supported by the data and nearly overlapped the ... | 2009 | 20738485 |
| expression of androgen receptor mrna in the ovary of japanese eel, anguilla japonica, during artificially induced ovarian development. | in order to elucidate how androgens may mediate their effects on ovarian growth, we investigated the mrna levels of two subtypes of androgen receptor (ara and arb) in the ovary of feminized japanese eel (anguilla japonica) during artificially induced ovarian development by quantitative real-time reverse transcriptase polymerase chain reaction and in situ hybridization. ara mrna levels were high from the late oil droplet stage to the late vitellogenic stage, whereas arb mrna levels were high from ... | 2010 | 20553719 |
| investigation on natural diets of larval marine animals using peptide nucleic acid-directed polymerase chain reaction clamping. | the stomach contents of the larvae of marine animals are usually very small in quantity and amorphous, especially in invertebrates, making morphological methods of identification very difficult. nucleotide sequence analysis using polymerase chain reaction (pcr) is a likely approach, but the large quantity of larval (host) dna present may mask subtle signals from the prey genome. we have adopted peptide nucleic acid (pna)-directed pcr clamping to selectively inhibit amplification of host dna for ... | 2011 | 20535520 |
| production of recombinant japanese eel gonadotropins by baculovirus in silkworm larvae. | recombinant follicle-stimulating hormone (refsh) and luteinizing hormone (relh) of the japanese eel anguilla japonica were produced by baculovirus in silkworm bombyx mori larvae. cdnas encoding japanese eel gonadotropin subunits (i.e., fsh beta, lh beta, and common alpha) were introduced into the baculovirus, which was infected into silkworm larvae after propagation of the recombinant virus in b. mori culture cells. a 100ml solution of pooled hemolymph from silkworm larvae containing refsh or re ... | 2010 | 20064515 |
| investigating expression profiles of vegf-flk, and angpt1 during development of gas glands in japanese eel (anguilla japonica). | angiogenesis is a highly regulated physiological process in animals. angiopoietin-1 (angpt1) induces the signaling pathways related to vessel maturation in late phase of angiogenesis, which recruits pericyte supplements to make compact interaction with vessel tubes. there are only few data showing angpt1 functions in fish. by using degenerate primers, partial sequence (812 bp) of angpt1 was cloned from anguilla japonica, and deduced amino acids showed 80% similarity to those of zebrafish. physio ... | 2010 | 19962446 |
| cloning and regulation of expression of the na+-cl--taurine transporter in gill cells of freshwater japanese eels. | our previous studies have demonstrated the hypertonic-induced expression of osmotic stress transcription factor and the regulatory volume increase (rvi) response in gill cells isolated from freshwater eels. in this study, we aimed to clone one of the organic osmolyte transporters, the na+-cl--taurine transporter (taut), and to characterize its expression in anisosmotic conditions, using both in vivo and in vitro approaches. a cdna clone encoding taut was isolated from gill tissues of japanese ee ... | 2009 | 19801424 |
| hox genes of the japanese eel anguilla japonica and hox cluster evolution in teleosts. | compared with other diploid teleosts (2n=48), anguilloid fish have a specialized karyotype (2n=38) and remarkable morphological variation, and represent one basal group species of teleosts. to investigate the hox gene/cluster inventory in basal teleosts, a pcr-based survey of hox genes in the japanese eel (anguilla japonica) was conducted with both gene-specific and homeobox-targeted degenerate primers. our data provide evidence that at least 34 distinct hox genes exist in the japanese eel genom ... | 2010 | 19670462 |
| the effects of seasonal and interannual variability of oceanic structure in the western pacific north equatorial current on larval transport of the japanese eel anguilla japonica. | as the north equatorial current (nec)-bifurcation is known to be related to el niño-southern oscillation (enso) events, the influence of the position of the nec bifurcation on transport success of the larval japanese eel anguilla japonica was investigated. using a lagrangian modelling approach, larval transport was simulated and the relative influence of el niño and la niña events and the nec-bifurcation position on the success of particle transport analysed. the number of particles transported ... | 2009 | 20735678 |
| sympatric spawning of anguilla marmorata and anguilla japonica in the western north pacific ocean. | extensive collections were made of the larvae of the temperate japanese eel anguilla japonica and the tropical giant mottled eel anguilla marmorata in an overlapping area of the north equatorial current region of the western north pacific ocean. collections of 189 a. marmorata and > 2500 a. japonica larvae during nine surveys from 1991 to 2007 showed that these two anguillid eels have similar spawning areas just west of the southern west mariana ridge. in july to august 2006 and august 2007, mor ... | 2009 | 20735676 |
| androgen action on hepatic vitellogenin synthesis in the eel, anguilla japonica is suppressed by an androgen receptor antagonist. | involvement of additional hormones other than estrogen in the control of vitellogenin (vg) synthesis has been suggested in fish. however, no satisfactory explanation on the mechanism of the action of these hormones has been reported. in this study, we have exploited the possibility of androgen receptor mediation during the androgen action on the pathway of vg synthesis. hepatocytes were prepared from sexually immature japanese eel anguilla japonica and treated with estradiol-17beta (e2), 17alpha ... | 2005 | 15878656 |
| oceanic migration and spawning of anguillid eels. | many aspects of the life histories of anguillid eels have been revealed in recent decades, but the spawning migrations of their silver eels in the open ocean still remains poorly understood. this paper overviews what is known about the migration and spawning of anguillid species in the ocean. the factors that determine exactly when anguillid eels will begin their migrations are not known, although environmental influences such as lunar cycle, rainfall and river discharge seem to affect their pat ... | 2009 | 20735675 |
| degradation of oxolinic acid and flumequine in aquaculture pond waters and sediments. | oxolinic acid (oa) and flumequine (flu) are two of the quinolone antibiotics (qas) that are widely used in aquaculture. the purpose of this study was to understand the fates of oa and flu in waters and sediment slurries from aquaculture ponds in a laboratory experiment. waters and sediments were sampled from an eel (anguilla japonica) pond and a shrimp (penaeus vannamei) pond. the effects of light, microbial activities, and temperature on the degradation of these two qas were elucidated. results ... | 2009 | 19230954 |
| roles of slc13a1 and slc26a1 sulfate transporters of eel kidney in sulfate homeostasis and osmoregulation in freshwater. | sulfate is required for proper cell growth and development of all organisms. we have shown that the renal sulfate transport system has dual roles in euryhaline eel, namely, maintenance of sulfate homeostasis and osmoregulation of body fluids. to clarify the physiological roles of sulfate transporters in teleost fish, we cloned orthologs of the mammalian renal sulfate transporters slc13a1 (nasi-1) and slc26a1 (sat-1) from eel (anguilla japonica) and assessed their functional characteristics, tiss ... | 2005 | 15802556 |
| rectal water absorption in seawater-adapted japanese eel anguilla japonica. | marine teleosts drink large amounts of seawater to compensate for continuous osmotic water loss. we investigated a possible significant role of the rectum in water absorption in seawater-adapted eel. in rectal sacs filled with balanced salt solution (bss) and incubated in isotonic bss, water absorption was greater in seawater-adapted eel than in freshwater eel. since rectal fluid osmolality was slightly lower than plasma osmolality in seawater-adapted eel, effects of rectal fluid osmolality on w ... | 2008 | 18687408 |
| antidiuretic effect of eel anp infused at physiological doses in conscious, seawater-adapted eels, anguilla japonica. | atrial natriuretic peptide (anp) is known as a potent natriuretic/diuretic hormone in vertebrates. however, eel anp infused at doses that did not alter arterial blood pressure (0.3-3.0 pmol/kg/min) decreased urine volume and increased urinary na concentration in seawater (sw)-adapted eels but not in freshwater (fw)-adapted eels. the renal effects were dose-dependent and disappeared after infusate was switched back to a vehicle (0.9% nacl). urinary na excretion (volume x na concentration) did not ... | 1998 | 18466004 |
| axoneme-dependent tubulin modifications in singlet microtubules of the drosophila sperm tail. | drosophila melanogaster sperm tubulins are posttranslationally glutamylated and glycylated. we show here that axonemes are the substrate for these tubulin c-terminal modifications. axoneme architecture is required, but full length, motile axonemes are not necessary. tubulin glutamylation occurs during or shortly after assembly into the axoneme; only glutamylated tubulins are glycylated. tubulins in other testis microtubules are not modified. only a small subset of total drosophila sperm axoneme ... | 2008 | 18205200 |
| identification of two insulin-like growth factor iis in the japanese eel, anguilla japonica: cloning, tissue distribution, and expression after growth hormone treatment and seawater acclimation. | to better understand the role of igfs in japanese eel, anguilla japonica, we cloned insulin-like growth factor-ii (igf-ii) cdnas and examined their mrna expression in several tissues. two eel igf-ii cdnas, eigf-ii-1 and eigf-ii-2, were cloned from the liver. a signal peptide and a mature peptide of both preproigf-iis were composed of 47 amino acids (aa) and 69 aa, but they differed at 17 aa and 13 aa, respectively. the e domain of eigf-ii-1 was 49 aa longer than that of eigf-ii-2, and differed a ... | 2008 | 17855139 |
| follicle-stimulating hormone induces spermatogenesis mediated by androgen production in japanese eel, anguilla japonica. | follicle-stimulating hormone (fsh) plays important roles in spermatogenesis. however, the biologic activity of fsh can vary in different vertebrate classes, and the definitive function of fsh has not been established. in this study, we investigated the functions of fsh on spermatogenesis using an in vitro culture system for japanese eel testis. the eel fsh receptor was expressed in testis tissue during the whole process of spermatogenesis, mainly by leydig cells that produce steroid hormones and ... | 2007 | 17761645 |
| differential expression and regulation of gonadotropins and their receptors in the japanese eel, anguilla japonica. | eel species have a striking life cycle with a blockade of puberty until the oceanic migration. we report the first molecular data on eel gonadotropin receptors. the partial sequences cloned covered two-third of the open reading frame and included most of the extracellular and transmembrane domains. phylogenetic analysis partitioned the two eel gonadotropin receptors into the two teleost fshr and lhr clusters, respectively. real-time quantitative rt-pcr was used to quantify the expression of eel ... | 2007 | 17597622 |
| effect of osmotic shrinkage and hormones on the expression of na+/h+ exchanger-1, na+/k+/2cl- cotransporter and na+/k+ -atpase in gill pavement cells of freshwater adapted japanese eel, anguilla japonica. | it is well-known that gill epithelial cells are important in fish osmoregulation. however, studies on the effect of osmotic stress on the direct cellular responses of the gill epithelial cells are limited. in this paper, we aimed to determine the effects of osmotic hypertonicity, hormones and cellular signaling molecules on the expression of ion transporters in the cultured primary freshwater pavement cells (pvcs), prepared from freshwater-adapted eels (anguilla japonica). our data demonstrated ... | 2007 | 17562884 |
| purification and characterization of a novel imidazole dipeptide synthase from the muscle of the japanese eel anguilla japonica. | we have purified a novel enzyme from eel white muscle which catalyzes the syntheses of imidazole dipeptides, such as carnosine (beta-alanyl-l-histidine), anserine (beta-alanyl-pi-methyl-l-histidine), and balenine (ophidine; beta-alanyl-tau-methyl-l-histidine), directly from their precursors. the enzyme was purified 1130-fold from eel muscle by a series of column chromatographies. although eel muscle contains a large amount of carnosine and only trace amounts of anserine and balenine, the anserin ... | 2007 | 17261377 |
| thyroid hormone receptor beta is widely expressed in the brain and pituitary of the japanese eel, anguilla japonica. | in a previous study, we cloned the thyroid hormone receptor betab (trbetab) from a teleostean fish, the japanese conger eel (conger myriaster). the gene encoding this receptor is expressed in the brain and pituitary. in this study, we cloned trbetab from the brain of the japanese eel (anguilla japonica) to extend our studies into thyroid hormone function in fish. rt-pcr analysis demonstrated that the trbetab transcripts were abundant in both the brain and pituitary. the trbetab cdna encoded a 37 ... | 2007 | 17150218 |
| roles of 11beta-hydroxysteroid dehydrogenase in fish spermatogenesis. | in fish spermatogenesis, the main action of progestins is generally regarded as the induction of sperm maturation. our previous in vitro study demonstrated that a progestin, 17alpha,20beta-dihydroxy-4-pregnen-3-one (dhp), induced the initiation of meiosis in spermatogenesis in the japanese eel (anguilla japonica). in the present study, to elucidate the molecular mechanisms underlying the action of dhp, we attempted to clone cdnas encoding genes whose expression was induced by dhp in eel testis, ... | 2006 | 16887910 |
| structural and expression analysis of hepatic vitellogenin gene during ovarian maturation in anguilla japonica. | vitellogenin (vtg), the precursor molecule for yolk, is synthesized in the liver under estrogenic control. in all oviparous species, including fish, the process of vitellogenesis is crucial to subsequent embryonic development. this study attempted to obtain the cdna encoding for vtg from female japanese eels, anguilla japonica. rapid amplification of cdna ends (race) and polymerase chain reaction (pcr) were used to amplify vtg cdna prepared from liver extracts. obtained pcr products were subclon ... | 2006 | 16854581 |
| expression of growth hormone family and growth hormone receptor during early development in the japanese eel (anguilla japonica). | in a previous study, we identified cdnas encoding the growth hormone receptor (eghr1) and eghr1 homologue (eghr2) in japanese eel (anguilla japonica). in the present study, changes in the developmental expression of growth hormone (gh), eghr1 and eghr2 were investigated in the japanese eel eggs and preleptocephali by rt-pcr and immunohistochemical methods in an attempt to examine the involvement of these proteins in larval growth. the gh transcripts and the production of gh protein were not dete ... | 2006 | 16828323 |
| an endothelial-cell-enriched primary culture system to study vascular endothelial growth factor (vegf a) expression in a teleost, the japanese eel (anguilla japonica). | a partial gene for eel (anguilla japonica) vascular endothelial growth factor (vegf) has been cloned and an endothelial-cell-enriched primary culture derived from rete mirabile established to study regulation of the expression of the eel vegf gene. cells were cultured in m199 medium containing 0.1% fetal calf serum (fcs) and serum-free m199 medium for long-and short-term experiments, respectively. cells were separately treated with cobalt ions (co2+), basic fibroblast growth factor (bfgf), and e ... | 2006 | 16807025 |
| in vitro induction of luteinizing hormone synthesis by estrogen in organ-cultured pituitary glands of the japanese eel, anguilla japonica. | an organ culture method for pituitary glands isolated from immature japanese eels (anguilla japonica) was developed. this method could conserve the histological features of the pituitary glands for at least 21 days. the ability to synthesize gonadotropic hormone (gth) in cultured eel pituitary glands was examined by detecting luteinizing hormone (lh) beta protein immunohistochemically. in a basal medium (leibovitz l-15), lh beta-immunoreactive cells were very scarce, but after addition of estrad ... | 2003 | 12560603 |
| purification and characterization of dermatan sulfate from the skin of the eel, anguilla japonica. | glycosaminoglycans were isolated from the eel skin (anguilla japonica) by actinase and endonuclease digestions, followed by a beta-elimination reaction and deae-sephacel chromatography. dermatan sulfate was the major glycosaminoglycan in the eel skin with 88% of the total uronic acid. the content of the idoa2salpha1-->4galnac4s sequence in eel skin, which shows anticoagulant activity through binding to heparin cofactor ii, was two times higher than that of dermatan sulfate from porcine skin. the ... | 2003 | 12543559 |
| cloning and characterization of a cdna encoding cholesterol side-chain cleavage cytochrome p450 (cyp11a1): tissue-distribution and changes in the transcript abundance in ovarian tissue of japanese eel, anguilla japonica, during artificially induced sexual development. | cholesterol side-chain cleavage cytochrome p450 (cyp11a1: p450scc) is a crucial steroidogenic enzyme that catalyzes an initial step in the production of all classes of steroids. a cdna encoding japanese eel p450scc was cloned and characterized. the cdna putatively encoded 521 amino acid residues with high homology to those of other vertebrate forms. the recombinant p450scc produced in cos-7 cells efficiently catalyzed the conversion of 25-hydroxycholesterol into pregnenolone. by northern blot, a ... | 2006 | 16616842 |
| [the study of ribosomal protein l15 cdna sequences as a molecular marker in the teleostei phylogenetic analysis]. | in this study, the full-length cdnas of rpl15 (ribosomal protein l15) gene were cloned and sequenced from fifteen fishes of five orders under teleostei. the complete orf sequences were analyzed for phylogenetic reconstruction for the first time to evaluate the potential of rpl15 gene as a novel marker in resolving teleostean phylogenetic relationships. the resultant nj, mp and ml trees with anguilla japonica as the outgroup were generally resolved and largely congruent with the morphology-based ... | 2006 | 16520312 |
| sequence and expression of androgen receptor and estrogen receptor gene in the sex types of protogynous wrasse, halichoeres trimaculatus. | sex steroid hormones play important roles in sex change and behavior of wrasses. their actions are considered to be mediated through the nuclear hormone receptors. in this study, to elucidate the roles of estrogen receptor (er) and androgen receptor (ar) in the reproduction of the protogynous wrasse, halichoeres trimaculatus, ar and er genes were partially cloned using 5'- and 3'-race and their transcript levels in the gonads and the brain were measured by competitive rt-pcr. the amino acid sequ ... | 2002 | 12383444 |
| [induction of pond-cultivated anguilla japonica gonadial development by controlling temperature in high temperature season]. | in this study, the pond-cultivated anguilla japonica was induced to mature by artificially controlling temperature at 18 +/- 2 degrees c in high temperature season (from june to september), with injection of hcg and cpe. the results showed that both the male and the female eel could be induced to mature, and the artificial maturation induction rate was 73.33% and 67.77%, while under non-controlling temperature 25 approximately 32 degrees c, the maturation induction rate was 0 and 33.33%, respect ... | 2005 | 16471368 |
| cloning and characterization of vitellogenin cdna from the common japanese conger (conger myriaster) and vitellogenin gene expression during ovarian development. | the major yolk protein precursor, vitellogenin (vtg) was detected in plasma from vitellogenic females and estradiol-17beta (e2)-treated immature females, but not in males and immature females by western blotting in common japanese conger conger myriaster. its molecular mass was approximately 180 kda under denaturing and reducing conditions. the common japanese conger vtg cdna was cloned from the liver of vitellogenic female. it contains 5110 nucleotides including an open reading frame that encod ... | 2006 | 16460978 |
| [modality and structure of japanese eel (anguilla japonica) during spermiogenesis]. | the special process and special structure which bring organelle during the spermiogenesis of japanese eel, anguilla japonica were observed by scanning electron microscope and transmission electron microscope. the process which spermatoblast became sperm including four special stages, the early stage, the middle stage, the later stage and the spermic stage, then came into being a normal mature sperm. in the early stage, cell nucleus became long form gradually by the oval form. in one side of the ... | 2009 | 19537199 |
| extracellular calcium-sensing receptor distribution in osmoregulatory and endocrine tissues of the tilapia. | the extracellular calcium-sensing receptor (casr) serves an important detector function in vertebrate ca(2+) homeostasis. in this study, we surveyed using immunohistochemistry the tissue and cellular distribution of the casr protein in the mozambique tilapia (oreochromis mossambicus) and the japanese eel (anguilla japonica). specifically, we examined receptor expression in ion-transporting barrier tissues that may be directly responsive to extracellular ca(2+) levels, and in tissues that are imp ... | 2009 | 19523399 |
| influence of water temperature and feeding regime on otolith growth in anguilla japonica glass eels and elvers: does otolith growth cease at low temperatures? | the influences of water temperature and feeding regime on otolith growth in anguilla japonica glass eels and elvers were investigated using individuals reared at 5, 10, 15, 20, 25 and 30 degrees c and in fed or unfed conditions at salinity 32 after their otoliths were marked with alizarin complexone (alc). to eliminate the difficulty of observing the edges of otoliths with optical (om) or scanning electron (sem) microscopes, three to 10 individuals were sampled from each tank at 10, 20 and 30 da ... | 2009 | 20735680 |
| antidipsogenic effects of eel bradykinins in the eel anguilla japonica. | a peptide with bradykinin (bk)-like immunoreactivity was isolated from an incubate of heat-denatured eel plasma with porcine pancreatic kallikrein. the purified peptide had the following amino acid sequence: arg-arg-pro-pro-gly-ser-trp-pro-leu-arg. this decapeptide, named eel [arg(0)]bk, was identical to two previously identified bk homologs from cod and trout. high conservation of the bk sequence among distant teleost species suggests an important function in this vertebrate group. bolus intra- ... | 2001 | 11557614 |
| apolipoprotein complexity in japanese eel anguilla japonica: truncated apolipoprotein a-i and apolipoprotein a-i-like protein in plasma lipoproteins. | a truncated apolipoprotein (apo) a-i with a molecular weight (m(r)) of 26 kda was first isolated from the plasma high density lipoproteins of an atypical japanese eel (anguilla japonica). interestingly, this eel contained a very small amount of intact apoa-i (m(r)28 kda) in the plasma, although serine protease inhibitors were present throughout the plasma preparation. the n-terminal sequence of 20 amino acids in truncated apoa-i was completely identical with that of intact apoa-i. another apolip ... | 2005 | 16306716 |
| "blood-contacting neurons" in the brain of the japanese eel anguilla japonica. | to discriminate "blood-contacting neurons" within the brain of the eel, evans blue (eb) was injected intraperitoneally. after five days, six brain areas were externally stained blue with the dye; the saccus dorsalis (sd), the epiphysis (e), the area postrema (ap), the posterior part of the magnocellular preoptic nucleus (pm), the pituitary (pit), and the saccus vasculosus (sv). among the eb-positive area, some cells in the pm, the anterior tuberal nucleus (nat) and the ap were discriminated as t ... | 2005 | 15828012 |
| a novel cysteine protease inhibitor with lectin activity from the epidermis of the japanese eel anguilla japonica. | a novel cysteine protease inhibitor (eel-cpi-1) was isolated from the epidermis of the eel. eel-cpi-1 was shown to bind strongly to both lactose- and carboxymethylated papain-affinity gels. its molecular mass under reducing condition was determined to be 18 kda by sds-polyacrylamide gel electrophoresis but approximately 30.5 kda under non-reducing-conditions. eel-cpi-1 inhibited papain (k(i)=18 nm) and ficin (k(i)=120 nm) competitively. combined with the data on amino acid and sequence analysis, ... | 2005 | 15820140 |
| natriuretic peptide guanylyl cyclase receptors in the kidney of the japanese eel, anguilla japonica. | natriuretic peptides are linked to osmoregulation, cardiovascular and volume regulation in fishes. the peptides bind to two guanylyl-cyclase-linked receptors, natriuretic peptide receptor-a (npr-a) and npr-b, to elicit their effects. atrial natriuretic peptide (anp) binds principally to npr-a, whereas c-type natriuretic peptide (cnp) binds to npr-b. the teleost kidney has an important role in the maintenance of fluid and electrolyte balance; therefore, the location of npr-a and npr-b in the kidn ... | 2005 | 15789218 |
| the effect of para-nonylphenol on japanese eel (anguilla japonica) spermatogenesis in vitro. | endocrine disrupters have been recognized to interfere with endocrine systems that regulate reproduction, for example, by mimicking or inhibiting the action of endogenous sex steroid hormones including estradiol-17beta (e2). in the present study, we examined the effect of an endocrine disrupter, para-nonylphenol (p-np) on spermatogenesis, and compared it with the action of e2, using an eel testicular organ culture system. p-np alone stimulated early spermatogonial renewal in the same manner as e ... | 2005 | 15642638 |
| effects of 4-tert-pentylphenol on the gene expression of p450 11beta-hydroxylase in the gonad of medaka (oryzias latipes). | alkylphenols including 4-tert-pentylphenol (4-pp) have been shown to alter sexual differentiation in fish due to their estrogenic properties. medaka (oryzias latipes) is so sensitive to these substances because morphological sex reversal and testis-ova induction are well developed in the exposed males. however, little work has been done to characterize the molecular effects of estrogenic substances on the morphological and gonadal feminization in male fish. cytochrome p450 11beta-hydroxylase (p4 ... | 2005 | 15642637 |
| isolation and characterization of active line and sines from the eel. | long interspersed elements (lines) and short interspersed elements (sines) are retrotransposons. these elements can mobilize by the "copy-and-paste" mechanism, in which their own rna is reverse-transcribed into complementary dna (cdna). lines and sines not only are components of eukaryotic genomes but also drivers of genomic evolution. thus, studies of the amplification mechanism of lines and sines are important for understanding eukaryotic genome evolution. here we report the characterization o ... | 2005 | 15548748 |
| a single amino acid substitution can shift the optimum ph of dnase i for enzyme activity: biochemical and molecular analysis of the piscine dnase i family. | we purified four piscine deoxyribonucleases i (dnases i) from anguilla japonica, pagrus major, cryprus carpio and oreochromis mossambica. the purified enzymes had an optimum ph for activity of approximately 8.0, significantly higher than those of mammalian enzymes. cdnas encoding the first three of these piscine dnases i were cloned, and the sequence of the takifugu rubripes enzyme was obtained from a database search. nucleotide sequence analyses revealed relatively greater structural variations ... | 2004 | 15182937 |
| structure and developmental expression of hatching enzyme genes of the japanese eel anguilla japonica: an aspect of the evolution of fish hatching enzyme gene. | we isolated seven cdna clones from embryos of the japanese eel anguilla japonica. each deduced amino acid sequence consisted of a signal peptide, a propeptide and a mature enzyme portion belonging to the astacin protease family. a phylogenetic analysis showed that the eel enzymes resembled the high choriolytic enzyme (hce) of medaka oryzias latipes, and the hatching enzymes of the zebra fish danio rerio and masu salmon oncorhynchus masou. hatching enzymes of these teleosts belonged to the group ... | 2004 | 15014992 |
| polymorphisms of ga/gt microsatellite loci from anguilla japonica. | six novel microsatellite loci, containing (ga)(15\n17) or (gt)(10\n19) perfect tandem repeats, were isolated and characterized for the catadromous eel anguilla japonica. the allelic size of the 6 loci ranged from 79 to 226 bp in length. all loci were polymorphic with a mean number of 14.7 alleles per locus and a mean heterozygosity of 0.67, suggesting higher polymorphism than that of freshwater and anadromous fishes, but lower than that of marine fishes. genotype diversity of the 6 loci ranged f ... | 2001 | 14961365 |
| cloning, sequencing, and phylogenetic analysis of complementary dna of novel cytochrome p-450 cyp1a in japanese eel (anguilla japonica). | complementary dna of cytochrome p-450 cyp1a, in addition to cyp1a1, has been isolated from japanese eel (anguilla japonica) liver treated with 3-methylcholanthrene. the cdna contained a 5' untranslated region of 66 bp, an open reading frame of 1554 bp coding for 517 amino acids and a stop codon, and a 3' untranslated region of 1166 bp. the predicted molecular weight of the japanese eel cyp1a was approximately 58.5 kda. the nucleotide sequence exhibited identities with the reported cyp1a1 sequenc ... | 2001 | 14961358 |
| serum estradiol-17beta and testosterone levels during silvering in wild japanese eel anguilla japonica. | to understand the changes of serum levels of sex steroids in the wild japanese eel anguilla japonica during silvering process, eels collected from the kaoping river of taiwan from august 2000 through june 2001 were examined. the maturational stages of female eels before and during silvering were divided into four stages: juvenile, sub-adult, pre-silver and silver stages based on skin coloration and oocyte diameter. male eels were investigated only in the silver stage. radioimmunoassays were empl ... | 2003 | 14662313 |
| interrenal steroid 21-hydroxylase in eels: primary structure, progesterone-specific activity and enhanced expression by acth. | cytochrome p450 21-hydroxylase (p450c21) is a key enzyme for corticosteroidogenesis. to understand the regulatory mechanisms of cortisol production in fish, we have cloned a cdna encoding p450c21, for the first time in non-mammalian vertebrates, from the head kidney of the eel (anguilla japonica). the overall similarity of the deduced p450c21 sequence was modest (41-44% amino acid identity) between the eel and mammals. however, the functional domains for steroid-binding, heme-binding and proton- ... | 2003 | 14519100 |
| profiles of pgh-alpha, gth i-beta, and gth ii-beta mrna transcript levels at different ovarian stages in the wild female japanese eel anguilla japonica. | the complete complementary dna (cdna) encoding pituitary gonadotropin ii-beta subunit (gth ii-beta) of japanese eel anguilla japonica was cloned and sequenced, and the profiles of pituitary glycoprotein hormone alpha subunit (pgh-alpha), gth i-beta, and gth ii-beta mrna transcript levels at different stages of ovarian development before vitellogenesis in the wild females were investigated. the maturity of female eels was divided into four stages: juvenile, sub-adult, pre-silver, and silver stage ... | 2003 | 12899842 |
| steroidogenic acute regulatory protein in eels: cdna cloning and effects of acth and seawater transfer on its mrna expression. | steroidogenic acute regulatory protein (star) is a key molecule for steroid production by translocating cholesterol from the outer to inner mitochondrial membrane. two cdnas of different length encoding star was cloned from the head kidney of the eel (anguilla japonica). in the 3'-untranslated region (utr) of the longer cdna, two putative polyadenylation signals were found. the shorter one differed from the longer one solely by the lack of middle of 3'-utr including the first polyadenylation sig ... | 2003 | 12655184 |
| c-type natriuretic peptide of rainbow trout (oncorhynchus mykiss): primary structure and vasorelaxant activities. | natriuretic peptides (nps) play important roles in osmoregulatory and cardiovascular systems of vertebrates. for functional studies of nps, rainbow trout (oncorhynchus mykiss), a euryhaline fish, is an interesting model. the information on homologous nps of salmonid fish is, however, still incomplete with respect to c-type np (cnp). in this study, we isolated cdnas encoding the precursor of cnp from the brain of trout. predicted mature cnp (cnp-22) sequence was identical to that of killifish fun ... | 2003 | 12568796 |
| ring finger, b-box, and coiled-coil (rbcc) protein expression in branchial epithelial cells of japanese eel, anguilla japonica. | an rbcc (ring finger, b-box, and coiled-coil) protein was identified that belongs to the superfamily of zinc-binding proteins and is specifically expressed in the gill of eel, anguilla japonica. euryhaline fishes such as eels can migrate between freshwater and seawater, which is considered to be accomplished by efficient remodeling of the architecture and function of the gill, a major osmoregulatory organ. to identify molecules involved in such adaptive changes, we performed differential display ... | 2002 | 12473111 |
| pseudodactylogyrus kamegaii sp. n. (monogenea: pseudodactylogyridae) from wild japanese eel, anguilla japonica. | the monogenean pseudodactylogyrus kamegaii sp. n. is described, based on specimens collected from the gills of wild japanese eel anguilla japonica caught in chiba prefecture, japan. this species is the most similar to p. anguillae (yin and sproston, 1948), but different in the shape and measurements of the male copulatory organ, vagina and marginal hook. this new species was collected from the eel in brackish waters, while p. anguillae and p. bini, the other known pseudodactylogyrids of japanese ... | 2002 | 12421631 |
| development of lateral line organs in leptocephali of the freshwater eel anguilla japonica (teleostei, anguilliformes). | a study of the ontogeny of the lateral line system in leptocephali of the japanese eel anguilla japonica reveals the existence of three morphologically different types of lateral line organs. type i is a novel sensory organ with hair cells bearing a single kinocilium, lacking stereocilia, distributed mainly on the head of larvae, and morphologically different from typical superficial neuromasts of the lateral line system. its developmental sequence suggests that it may be a presumptive canal neu ... | 2002 | 12219345 |
| three mrna species for mammalian-type gonadotropin-releasing hormone in the brain of the eel anguilla japonica. | a variant mrna species for mammalian-type gonadotropin-releasing hormone (mgnrh) that retains first intron has recently been found in the brain of a primitive teleost, the eel anguilla japonica. here we have found that this mrna species is generated from an alternative upstream transcription start site of the mgnrh gene. in addition, the upstream start site produces another mrna species that lacks first intron. both of these two variant mrna species, however, have the same open reading frame as ... | 2002 | 12088863 |
| the natriuretic peptide system in eels: a key endocrine system for euryhalinity? | the natriuretic peptide system of a euryhaline teleost, the japanese eel (anguilla japonica), consists of three types of hormones [atrial natriuretic peptide (anp), ventricular natriuretic peptide (vnp), and c-type natriuretic peptide (cnp)] and four types of receptors [natriuretic peptide receptors (npr)-a, -b, -c, and -d]. although anp is recognized as a volume-regulating hormone that extrudes both na(+) and water in mammals, anp more specifically extrudes na(+) in eels. accumulating evidence ... | 2002 | 11893596 |
| molecular cloning and characterization of growth hormone receptor and its homologue in the japanese eel (anguilla japonica). | two cdnas encoding growth hormone receptor (ghr)-like genes, eghr1 and eghr2, were isolated from japanese eel (anguilla japonica) liver tissue. the putative eel ghr proteins showed conserved structural features of vertebrate ghrs, including six cysteine residues and a ygefs motif in the extracellular domain, a single transmembrane region, and proline-rich box 1 and box 2 domains. northern blot analysis showed a single eghr1 transcript in liver, while two sizes of eghr2 transcripts, thought to be ... | 2006 | 16458558 |
| changes in hepatic vitellogenin mrna levels during oocyte development in the japanese eel, anguilla japonica. | the induction of vitellogenesis is a complex process requiring coordinated control and expression of many hepatic gene products, such as vitellogenin (vtg). to investigate the regulation of vtg synthesis, knowledge of the molecular genetics of vtg is required. here, the authors have isolated a partial cdna encoding japanese eel vtg using an immunoscreening technique. this cdna contained an open reading frame of 1629 bp, predicted to encode 543 amino acid residues, the sequence of which showed hi ... | 2002 | 11825029 |
| structure, properties and enhanced expression of galactose-binding c-type lectins in mucous cells of gills from freshwater japanese eels (anguilla japonica). | using a japanese-eel (anguilla japonica) gill cdna subtraction library, two novel beta-d-galactose-binding lectins were identified that belong to group vii of the animal c-type lectin family. the eel c-type lectins, termed ecl-1 and ecl-2, are simple lectins composed of 163 amino acid residues, including a 22-residue signal peptide for secretion and a single carbohydrate-recognition domain (crd) of approximately 130 residues typical of c-type lectins. the galactose specificity of the crd was sug ... | 2001 | 11695997 |
| identification of anguilla japonica and a. marmorata elvers by allozyme electrophoresis | in taiwanese waters, the morphologically similar elvers of anguilla japonica and a. marmorata can be distinguished easily at the following loci examined: ck-d*, ldh-b*, smdh-a* and smdh-b*. among these, ck-d* and ldh-b* have fixed allelic differences which can be used as a synoptic key for easy discrimination of the elvers of these two species. | 1997 | 9236101 |
| biofilter treatment of aquaculture water for reuse applications. | biotreatment of aquaculture water for recirculation purposes is a sensible mean to support the further growth of aquaculture industry without excessive water demands that are environmentally unsustainable. this study evaluates the efficacy of biofilter treatment of an eel (anguilla japonica) culture pond water using different filter media and flow scheme arrangements. the experimental results demonstrate that biofilter systems packed with suitable filter media are capable of improving the qualit ... | 2001 | 11487106 |
| high density lipoprotein binding protein of eel (anguilla japonica) liver with specificity of binding to apoai as a ligand. | high-density lipoprotein (hdl) binding protein (hbp) was isolated from the microsomal fraction of eel liver homogenate by affinity chromatography with a hdl-column. after sds-page and blotting, hbp on the pvdf membrane was detected by fitc-labeled hdl and apolipoprotein ai (apoai) as a ligand. hbp in the microsomal fraction was most abundant among microsomal, mitochondrial and cytosolic fractions. the hbp isolated by a hdl-column consisted of at least three proteins with low molecular weights of ... | 2001 | 11435139 |
| two subtypes of androgen and progestogen receptors in fish testes. | two subtypes (alpha and beta) of androgen (ar) and progestogen receptors (pr) are present in the testis of japanese eel (anguilla japonica). amino acid homology of the open reading frames between alpha and beta in ar or pr is approximately 40%, but the dna- and ligand-binding domains show high homology between subtypes. judging from these structures, alpha and beta are not isoforms derived from translational initiation at two in-phase atg codons, alternative splicing, or tetraploidy. in transien ... | 2001 | 11399479 |
| the novel sequences of major plasma apolipoproteins in the eel anguilla japonica. | cdnas encoding major plasma apolipoproteins (apo) were cloned from the eel anguilla japonica liver and their nucleotide sequences determined. sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that eel lipoproteins contain apolipoproteins of 28 kda and 14 kda as major components. each of the two apolipoproteins showed two isoforms having different isoelectric points as demonstrated by two-dimensional electrophoresis. the two 28 kda components had different n-terminal amino acid s ... | 2001 | 11278178 |
| immunocytochemical localization of taurine in the fish retina under light and dark adaptations. | previously we have observed the lack of immunoreactivity of taurine in the rod outer segments from light-adapted fish, such as the ayu plecoglossus altivelis and lefteye flounder paralichthys olivaceus. this finding prompted us to investigate if there is a difference in the immunocytochemical localization of taurine in the rod outer segments between the dark- and light-adapted states. in the retinas of the glass eel anguilla japonica and the young goldfish carassius auratus, extremely intense im ... | 2000 | 11140362 |
| effects of cortisol on chloride cells in the gill epithelium of japanese eel, anguilla japonica. | the purpose of the present study was to determine the effects of cortisol on the development of the freshwater chloride cell (cc), using flow cytometry. scanning electron microscopy was used to determine the corresponding modifications in cc apical structure. simultaneously, biochemical analyses were conducted to determine the activities of transport atpases, mitochondrial enzymes (succinate dehydrogenase (sdh) and mg(2+)-atpase) and lactate dehydrogenase (ldh). the effects of daily i.m. injecti ... | 2001 | 11139782 |
| role of the renin-angiotensin system in drinking of seawater-adapted eels anguilla japonica: a reevaluation. | the role of ang ii, a potent dipsogenic hormone, in copious drinking of seawater eels was examined. sq-14225 (sq), an angiotensin-converting enzyme inhibitor, infused intra-arterially at 0.01-1 microgram. kg(-1). min(-1), depressed drinking and arterial blood pressure in a dose-dependent manner. the inhibition was accompanied by a small decrease in plasma ang ii concentration, which became significant at 1 microgram. kg(-1). min(-1). after the infusate was changed back to the vehicle, the depres ... | 2000 | 10956272 |
| an eel cytochrome p450 1a gene having no xre sequences in its 5' upstream region of 1600 bp. | the gene family cytochrome p450 (cyp) 1a is ubiquitous among animals, and cyp1a1 genes have been identified in teleost and mammals. we isolated another cyp1a gene, which is inducibly expressed by exposure to 3-methylcholanthrene, from the genomic library of the eel (anguilla japonica). the genomic clone obtained, approximately 17,500 bp in length, contained the structural gene of the cyp1a and a 5' upstream region of about 1600 bp. sequence analysis of the 5' upstream region and the first and se ... | 2000 | 10811956 |
| protease activity appeared after trypsin treatment of the purified vitellogenin from eel anguilla japonica. | density gradient ultracentrifugation and anion-exchange chromatography combination were effective for the purification of the eel vitellogenin from the plasma of estradiol-treated eels. the vitellogenin was very high density glycolipoprotein (p = 1.27 g/ml) and its apolipoprotein was m(r) 196 k in both reduced and non-reduced conditions by sds-page. the major lipid component was phospholipid. the n-terminal amino-acid sequence of the vitellogenin was as follows: (ac)thr-pro-ala-leu/ala-asp-tyr. ... | 1996 | 8829806 |
| pathological changes caused by cold-water stress in japanese eel anguilla japonica. | in the present study, histopathological changes in japanese eel anguilla japonica subjected to 'cold-water stress' were examined. eels were exposed to cold water (13 to 15 degrees c) and warmer water (25 degrees c) as controls. fish held in warm water did not show any apparent changes. although none of the eels exposed to cold water died, they displayed nephrotic changes such as cloudy swelling and hyaline droplet degeneration of the renal tubular epithelia. fish with nephroses had low levels of ... | 2000 | 10785862 |
| molecular cloning and characterization of japanese eel ovarian p450c17 (cyp17) cdna. | as a first step in investigating the mechanism underlying the steroidogenic shift from the production of ovarian androgens (vitellogenic stage) to that of 17alpha-hydroxylated progestins (maturational stage) in japanese eel during induced oogenesis, a cdna encoding japanese eel (anguilla japonica) ovarian p450c17 (cyp17: steroid 17alpha-hydroxylase/c(17-20) lyase) was cloned and sequenced. this cdna contained the complete coding region representing 510 amino acid residues, which showed high sequ ... | 2000 | 10753574 |
| molecular cloning of fresh water and deep-sea rod opsin genes from japanese eel anguilla japonica and expressional analyses during sexual maturation. | we have determined the complete cdna sequences of fresh water rod opsin gene (fwo) and deep-sea rod opsin gene (dso) from japanese eel anguilla japonica. the cdna clones of fwo and dso consisted of 1437 and 1497 nucleotides, respectively. the predicted opsins of both genes consisted of 352 amino acid residues. southern blot and pcr analyses of genomic dna indicated that the japanese eel genome contains only one fwo and one dso and they are intronless. quantitative rt-pcr analyses revealed that t ... | 2000 | 10708752 |
| purification, characterization, and bioassay of prolactin and growth hormone from temperate basses, genus morone. | prolactin (prl) and two variants of growth hormone (gh), purified from pituitaries of striped bass (morone saxatilis) and its hybrid with white bass (m. saxatilis x m. chrysops) by gel filtration chromatography under alkaline conditions followed by reversed-phase high pressure liquid chromatography, appear similar between species. both the minor (gh i) and the major (gh ii) forms of purified gh appeared as single bands (m(r) approximately 23,000) after sodium dodecyl sulfate-polyacrylamide gel e ... | 2000 | 10620430 |
| estradiol-17beta stimulates the renewal of spermatogonial stem cells in males. | in this work, we examined the functions of the female hormone "estrogen" on spermatogenesis of the japanese eel (anguilla japonica). estradiol-17beta (e(2)), a natural estrogen in vertebrates, was present in the serum and its receptor was expressed in the testis during the whole process of spermatogenesis. spermatogonial stem cell renewal was promoted by e(2) implantation but was suppressed by tamoxifen (an antagonist of estrogen). in vitro, 10 pg/ml of e(2) was sufficient to induce spermatogoni ... | 1999 | 10527870 |
| growth hormone (gh)-dependent hepatic gh receptors in the japanese eel, anguilla japonica: effects of hypophysectomy and gh injection. | control mechanisms of growth hormone (gh) receptors in the eel liver were examined by following the time course of changes in total (mgcl2-treated membranes) and free (untreated membranes) gh-binding sites after hypophysectomy and replacement therapy with homologous gh. both total and free binding sites decreased significantly 1 week after hypophysectomy. scatchard analysis indicated that the reduction in gh receptors was primarily due to a decrease in the number of binding sites, rather than to ... | 1992 | 1577242 |