PMID(sorted ascending)
regeneration of lateral line and inner ear vestibular cells.labelling experiments with [3h]thymidine demonstrate a continuous production of cells in the mechanoreceptive lateral line organs of the eel (anguilla anguilla) and butterfly fish (pantodon buchholzi) as well as in the electroreceptive ampullary organ of the transparent catfish (kryptopterus bicirrhus). shortly after [3h]thymidine injection many cells are labelled in the middle and basal parts of the sensory organ and after a few days' survival sensory cells are also labelled. the vestibular sen ...19911752161
histochemical, connectional and cytoarchitectonic evidence for a secondary reduction of the pretectum in the european eel, anguilla anguilla: a case of parallel evolution.there are at least three different patterns of pretectal organization in teleost fishes: a simple pattern observed in cyprinids, an elaborate pattern present in percomorphs, and an intermediately complex pattern seen in many other teleost groups. the taxonomic distribution of the pretectal patterns indicates that the simple and the elaborate patterns are both evolutionarily derived (apomorphic) from the primitive (plesiomorphic) intermediately complex one. in anguillids, the pretectal pattern ob ...19911764633
in vivo and in vitro toxicity of fractionated fish lipids, with particular regard to their content of chlorinated organic compounds.six different lipid matrices (the intact lipid (il), four lipid fractions with different polarity, and the free fatty acids (ffas) obtained by hydrolysis of the triacylglycerol (tag) containing fraction) were obtained from salmon (salmo salar) and eel (anguilla anguilla), each collected at a contaminated and a comparatively uncontaminated catch site along the coast of scandinavia. the lipid matrices were studied in toxicological test systems representing various biological functions of different ...19911766922
regulation of secretion of the teleost fish hormone stanniocalcin: effects of extracellular calcium.the release in vivo and in vitro of stanniocalcin (stc) from the corpuscles of stannius (cs) of the rainbow trout and the european eel was studied. intraperitoneal injection of cacl2 (2.45 fish) leads to an elevation of both ionic and total calcium in the plasma and results in the release of stc from the cs into the blood. release of stc in vitro is not affected at "physiological" (1.0-1.5 mm) or lower ca2+ levels in the incubation medium. high levels of ca2+ (2.5 mm and higher), howev ...19911778405
effects of 17 beta-estradiol and carp gonadotropin on vitellogenesis in normal and hypophysectomized european silver female eel (anguilla anguilla l.) employing a homologous radioimmunoassay for vitellogenin.the european silver eels are at the early stages of vitellogenesis before the marine reproductive migration. vitellogenesis was induced by 17 beta-estradiol (e2) alone and by a purified carp gonadotropin (cgth). we studied and compared their effects on plasma vitellogenin (vg) levels and ovarian yolk contents in female normal (n) and hypophysectomized (h) eels for both treatments. to this purpose an homologous radioimmunoassay (ria) was established. eel vg was purified to homogeneity on 0.1% sds ...19911783271
prostaglandins in the kidney, urinary bladder and gills of the rainbow trout and european eel adapted to fresh water and seawater.prostaglandins in kidney, gills, and urinary bladder of freshwater-adapted and seawater-adapted rainbow trout, oncorhynchus mykiss (= salmo gairdneri), and european eel, anguilla anguilla, were determined by solid-phase extraction of tissue homogenates and high-pressure liquid chromatography. prostaglandins e2, e1, f1 alpha, f2 alpha, and d2 and the more stable metabolite of prostacyclin, 6-keto f1 alpha, occurred in these osmoregulatory tissues. in gill filaments and kidneys of both eel and tro ...19911783277
in vitro study on the impact of fish sera on the survival and fine structure of the eel-pathogenic acanthocephalan paratenuisentis ambiguus.the effects of fish sera on the growth and fine structure of infective larvae of the eel-pathogenic acanthocephalan paratenuisentis ambiguus (eoacanthocephala: tenuisentidae) were studied under in vitro conditions using sera from the final host anguilla anguilla and from two accidental fish hosts as well as fetal calf serum. as controls larvae were also kept in medium in the absence of serum and in experimentally infected eels. sera from the accidental fish hosts carp and rainbow trout exerted t ...19911805215
occurrence of acanthocephalus clavula (acanthocephala) in echinogammarus pungens (amphipoda) from the river adige.cystacanths of acanthocephalus clavula dujardin 1845 (acanthocephala) were found in the hemocoels of naturally infected echinogrammarus pungens m. edwards 1840 (amphipoda). crustaceans were collected in porto frossone, an estuarine locality of the river adige. only 3 out of 562 e. pungens specimens were infected by a. clavula cystacanths; the larvae were enclosed in a thin acellular envelope. infected amphipods were all females, and their total length was greater than that of uninfected females. ...19911844501
potential interactions between acanthocephalus anguillae and pomphorhynchus laevis in their natural hosts chub, leuciscus cephalus and the european eel, anguilla anguilla.chub and eels were experimentally infected via intermediate hosts harbouring cystacanths, with pomphorhynchus laevis alone, or acanthocephalus anguillae alone, or simultaneously with mixtures of both species in varying proportions, and sampled at 7, 56 or 112 days post-infection. examination of chub revealed that both species showed low establishment and growth rates, differing markedly from british field data, where chub is apparently one of the most important hosts, and preventing further mean ...19911852495
the primary structure of glucagon-like peptide but not insulin has been conserved between the american eel, anguilla rostrata and the european eel, anguilla anguilla.insulin was isolated from the pancreas of the american eel, anguilla rostrata, and its primary structure was established as (formula: see text). eel insulin contains unusual substitutions at b-21, b-22, and b-26 in the putative receptor-binding region of the molecule compared with other mammalian and fish insulins. the a-chain of insulin from the european eel contains an asparagine rather than a serine residue at position a-12. similarly, amino acid composition data indicate the b-chain of insul ...19911874385
regulation of the type-ii gonadotrophin alpha and beta subunit mrnas by oestradiol and testosterone in the european eel.the gonadotrophic function of the european eel (anguilla anguilla l.) at the silver stage is very weak: gonadotrophin-releasing hormone (gnrh) secretion is deficient and, moreover, dopamine inhibition overrides gnrh action. at the silver stage, oestradiol stimulates the biosynthesis of the type-ii gonadotrophin (gth-ii). to study the molecular mechanism of this activation further, we examined the effect of testosterone and oestradiol administration on pituitary levels of mrna encoding gth-ii alp ...19911892544
[purification and characterization of presumed thyrotropic hormone subunits of a teleost fish, the eel (anguilla anguilla)].we have only a partial knowledge of fish thyrotropins (tsh) and no data about peptide sequence are available. various hplc techniques allowed us to purify a 31.4 kda, heterodimeric protein from saline eel pituitary extracts containing tsh activity. partial n-terminal sequence (24 amino acids) from one subunit was strictly identical to that of eel gonadotropin ii (gth ii) alpha subunit. with regard to the second subunit, 41% of the 22 amino acids identified at the n-terminus were homologous to th ...19911933511
effects of hyperbaric pressure and temperature on atria from ectotherm animals (rana pipiens and anguilla anguilla).1. spontaneously beating atria from frogs (r. pipiens) and eels (a. anguilla) were compressed hydraulically to 10 mpa. effects on beating frequency and twitch tension were studied. 2. at low temperatures (8-10 degrees c) compression to 10 mpa caused a slowing of the beat frequency. no effects were noted at higher temperatures (16-24 degrees c). twitch tension was decreased by pressure at low temperatures and increased at high temperatures. 3. differences were noted between preparations from cold ...19901968818
induction of biotransformation in the liver of eel (anguilla anguilla l.) by sublethal exposure to dinitro-o-cresol: an ultrastructural and biochemical study.structural and functional alterations in hepatocytes of the european eel, anguilla anguilla, following a 4-week-exposure to 5, 50, and 250 micrograms/liter dinitro-o-cresol (dnoc) were investigated by means of electron microscopy and biochemistry and compared to liver pathology in eels exposed to the chemical spill into the rhine river at basle in november 1986. whereas phenological parameters (growth, condition factor) are unaffected, ultrastructural and biochemical alterations are detectable a ...19912065626
co2 back-diffusion in the rete aids o2 secretion in the swimbladder of the order to estimate the relative importance of back-diffusion of o2 and co2 for their partial pressure enhancement in the swimbladder, we have determined o2 and co2 partial pressure and content and ph in microsamples collected non-obstructively from the afferent and efferent rete vessels in the european eel. 1. the po2 increased significantly along the arterial vessels of the rete (from 33 to 303 torr), with no change in o2 content, suggesting o2 not to be exchanged in the rete counter-current ...19902113304
molecular cloning and sequence analysis of the cdna for the putative beta subunit of the type-ii gonadotrophin from the european eel.oestradiol treatment enhances type-ii gonadotrophin (gth-ii) synthesis in the european eel (anguilla anguilla) at the silver stage. as a first step in studying the molecular mechanisms involved in this stimulation, we cloned and characterized the cdna encoding the beta subunit of eel gth-ii. a cdna library was constituted in lambda gt10 from oestradiol-treated eels. it was screened using an oligodeoxyribonucleotide mixed probe designed to be complementary to a highly conserved region of cdnas fr ...19902116136
lysine transport by brush-border membrane vesicles of eel intestine: interaction with neutral amino acids.l-[3h]lysine uptake was measured in brush-border membrane vesicles prepared from intestinal mucosa of the european eel anguilla anguilla. lysine uptake occurred via 1) a nonsaturable component with an apparent diffusional permeability (p) of 0.58 protein-1.min-1,2) a na-dependent transport system [half-saturation constant (kapp) 0.16 mm, maximal transport rate (jmax) 3.57 protein-1.min-1]; 3) a na-independent transport system (kapp 0.17 mm, jmax 2.77 protein-1.min-1 ...19902124427
chromatographic and immunological evidence for mammalian gnrh and chicken gnrh ii in eel (anguilla anguilla) brain and pituitary.gonadotropin-releasing hormone (gnrh) peptides in the brain and pituitary of the european eel (anguilla anguilla) were investigated by reverse phase high performance liquid chromatography (hplc) and radioimmunoassay with region-specific antisera. two gnrh molecular forms were demonstrated in brain and pituitary extracts. one form eluted in the same position as synthetic mammalian gnrh on hplc and was recognized by antibodies directed against the nh2 and cooh termini of mammalian gnrh as well as ...19902199948
metabolic effects of kraft mill effluents on the eel anguilla anguilla l.yellow eels (anguilla anguilla l.) with an average weight of 60 g were used in this experiment. the fish were caught in june/july at the aveiro lagoon on the portuguese west coast, transported to the department of biology, aveiro university, and kept in aerated aquaria for 1 week before the experiment started. the eels were then exposed for 1 and 3 weeks to 75 and 50% of the kraft pulp mill effluent. the eels exposed to the kraft pulp mill effluent developed an increase in red blood cell number ...19902226239
influence of inorganic lead on the biochemical blood composition of the eel, anguilla anguilla l.yellow eels (anguilla anguilla l.) with an average weight of 50 g were caught in september in the aveiro lagoon on the portuguese west coast and kept in aerated aquaria for 1 week before the experiment started. the eels were exposed to an inorganic lead concentration of 300 micrograms pb/liter for 30 days. differential white blood cell count showed an increase in the number of lymphocytes in exposed fish. blood hemoglobin and number of red blood cells per cubic millimeter showed no differences b ...19902226244
an experimental study of the retinal projections of the european eel (anguilla anguilla), carried out at the catadromic migratory silver stage.a radioautographic study of the european eel (anguilla anguilla) was carried out in ten female specimens at the catadromic migratory silver stage. terminal arborizations of contralaterally projecting visual fibres were identified in ten hypothalamic structures (area optica preoptica ventralis and the nuclei suprachiasmaticus, opticus hypothalamicus ventromedialis, preopticus magnocellularis lateralis, posterioris lateralis, posterioris dorsalis periventricularis posterioris dorsalis lateralis, p ...19902254656
myosin structure in the eel (anguilla anguilla l.). demonstration of three heavy chains in adult lateral muscle.myosin extracts from central white fibers and peripheral red fibers of the lateral muscle of eel (anguilla anguilla) were analysed by electrophoresis under non-dissociating conditions, which demonstrated a polymorphism of myosin isoforms. the light and heavy subunit content of the isomyosins was established using sds-page and two-dimensional electrophoresis. in the central white muscle, 3 myosin isoforms fm3, fm2, fm1, were characterized by 3 types of fast light chain and one fast heavy chain hc ...19902269355
[hormonal stimulation, in vivo, of the ovary of european eel in the yellow stage].the immature ovary of yellow eel was stimulated by a long-term treatment with a gonadotropin ii rich extract of carp pituitary. ovarian follicles of treated yellow eels showed an accumulation of lipidic vacuoles in the oocyte cytoplasm and a thickened follicular envelope (in this regard, they resembled the ovarian follicles of previously studied silver eels). the treatment also resulted in a significant but limited increase in the gonadosomatic ratio and mean follicle size (these values were muc ...19902291806
[regional and recent trends in the chlorinated hydrocarbon levels in eels from berlin waters].during the five year period from early 1982 to 1986, we engaged in research concerning the chlorinated hydrocarbon content of eels (anguilla anguilla l.) in the limnic water ecosystem of berlin (west). the total count of analytical samples, taken at 11 different sampling points, comprised 370 samples, divided up into 41 collectives. each fish was checked individually for the patterns of contamination with chlorinated hydrocarbons, especially ddt-, bhc-, and pcb-related compounds. the various are ...19902353916
the na(+)-dependent proline carrier, of eel intestinal brush-border membrane, sequentially binds proline and then na+.the mechanism of na+/l-proline cotransport, present on brush-border membrane (bbm) vesicles of the european eel intestine, was studied. initial cotransport rates, depending on increasing proline and na+ concentrations in the extravesicular medium (zero-trans conditions), were measured by monitoring the decay of an inside-negative membrane potential, i.e. the fluorescence quenching of the voltage-sensitive cyanine dye 3,3'-diethylthiacarbocyanine iodide (dis-c2(5)). by simultaneously estimating t ...19902397223
on the heterogeneity of purkinje neurons in vertebrates. cytochemical and morphological studies of chromatin during eel (anguilla anguilla l.) life cycle.the relationship between the heterogeneity of purkinje cell chromatin and the functional involvement of cerebellum has been analyzed comparing two stages of eel life cycle (yellow eel and silver eel) which are characterized by a different degree of swimming activity. the dna content and the chromatin condensation have been studied by means of microdensitometry (feulgen-dna, feulgen-dna/area), microfluorometry (dna after intercalation with propidium iodide at low and high concentration) and elect ...19852410490
estradiol has inverse effects on pituitary glycoprotein hormone alpha-subunit messenger ribonucleic acid in the immature european eel and the gonadectomized teleosts, the pituitary contains a single glycoprotein gonadotropic hormone (gth) composed of two dissimilar alpha- and beta-subunits. the european eel, anguilla anguilla l, is sexually immature at the silver stage due to a deficiency in gth synthesis and secretion. in previous studies we (s.d., ya.f.) have demonstrated a strong stimulatory action of estradiol (e2) on eel pituitary gth content. in contrast, we (r.c., m.j.) have shown that in the rat e2 negatively regulates gonadotropin subuni ...19872441980
localization of beta-hydroxysteroid dehydrogenase in anguilla anguilla testis.the histochemical reaction for 3 beta-hydroxysteroid dehydrogenase was applied to glutaraldehyde fixed eel testis and successively processed for transmission electron microscopy. the reaction product was found only on the smooth endoplasmic reticulum and in the intermembrane space of mitochondria of the leydig cells of hcg treated silver eels. the positive cytochemical reaction appears to be coupled with an enlargement of the leydig cells and an increase of their smooth endoplasmic reticulum.19872443116
acute toxicity of organochlorined pesticides to the european eel, anguilla anguilla: the dependency on exposure time and temperature. 19872444293
distribution and morphological characteristics of efferent neurons innervating end organs in the ear and lateral line of the european eel.neurons that provide the efferent innervation to the labyrinthine and lateral line sense organs of the eel were located by applying horseradish peroxidase to branches of the appropriate cranial nerves. retrogradely labeled neurons were found in a single median column, the octavolateralis efferent nucleus (oen), located immediately rostral to and overlapping with the facial nucleus of the branchiomotor column. we estimate that on each side of the brain the efferent nucleus contains about 60-70 ne ...19872448346
distribution of afferent fibers in the brainstem from end organs in the ear and lateral line in the european eel.sensory nerve fibers from the lateral line system and labyrinth of anguilla anguilla were labeled with horseradish peroxidase and traced to various targets in the ipsilateral brainstem. the three rami of the anterior lateral line nerve and the supratemporal ramus of the posterior lateral line nerve form overlapping terminal zones in the ventral portion of nucleus medialis. the posterior lateral line nerve on the body is represented exclusively in the dorsal half of the nucleus medialis. eighth n ...19872448347
lethal toxicity of lindane on a teleost fish, anguilla anguilla from albufera lake (spain): hardness and temperature effects.this paper reports the results of toxicity tests conducted using anguilla anguilla under three different water temperature (15, 22 and 29 degrees c) and two hardness regimes (250 and greater than 600 ppm caco3). the 96-h lc50 increased in the experimental medium (p less than 0.05) by an order of magnitude from 0.32 to 0.45 mg/l between 15 and 29 degrees c. however in the natural medium it is similar (p greater than 0.05) (0.54 to 0.55 mg/l) for these same temperatures. the toxicity of lindane on ...19882453551
influence of protein content of diet on growth and lipid composition of european eel muscle and liver.the influence of diet protein content (35-45-55%) on growth and lipid composition of muscle and liver of european eel (anguilla anguilla) was studied for the first time. in control eel, triacylglycerols constituted about 90% of total lipids in muscle and about 40% in liver. triacylglycerol content in eel muscle significantly increased after two months of treatment with any diet assayed, with independence of protein content and source. in liver, this increase was comparatively higher in herring m ...19892475082
microhabitats of monogenean gill parasites on european eel (anguilla anguilla).the distribution of adult pseudodactylogyrus anquillae and p. bini and postlarvae was recorded on glass-eels and pigmented eels of different size and infection intensity. the two species occupied different microhabitats on the host's gill apparatus but the preferred sites depended partly on host size. postlarval migration was indicated. mortality of young parasites, reinforcement of reproductive barriers and competition seems to be less likely explanations of the spatial distribution.19892488048
distribution and pharmacological properties of the gabaa/benzodiazepine/chloride ionophore receptor complex in the brain of the fish anguilla the present study, we characterized the distribution and the pharmacological properties of the different components of the gabaa receptor complex in the brain of the eel (anguilla anguilla). benzodiazepine recognition sites labeled "in vitro" with [3h]flunitrazepam ([3h]fnt) were present in highest concentration in the optic lobe and in lowest concentration in the medulla oblongata and spinal cord. a similar distribution was observed in the density of gamma-[3h]aminobutyric acid ([3h]gaba) bi ...19892538558
saccharide residues in human gingiva as revealed with fluorochrome-coupled lectins.the histochemical binding of 16 fluorochrome-conjugated lectins to human marginal gingiva was investigated. of a total of 14 galactose/n-acetylgalactosamine (gal/galnac)-specific lectins, dolichos biflorus (dba), helix pomatia (hpa), and helix aspersa agglutinins (haa) were blood group a-reactive whereas griffonia simplicifolia i-b4 (gsa-i-b4) and sophora japonica (sja) agglutinins were blood group b-reactive. hpa, haa and gsa-i-b4 bound to all suprabasal epithelial cells and to vascular endothe ...19892542513
solute back-diffusion raises the gas concentrating efficiency in counter-current flow.we have extended the counter-current model of the rete mirabile of the fish swimbladder to include the effects of inert gas secretion into the swimbladder as well as solute back-diffusion in the rete capillaries. (1) gas secretion attenuates the inert gas concentrating efficiency of the rete, i.e. its ability to produce high inert gas partial pressures in blood at the swimbladder pole. the maximum attainable gas secretion rate depends on the salting-out effect, i.e. on the ratio of solubility in ...19892554452
na-dependent l-glutamate transport by eel intestinal bbmv: role of k+ and cl-.l-[3h]glutamate uptake into eel (anguilla anguilla) intestinal brush-border membrane vesicles (bbmv) was a sigmoidal function of extravesicular na, suggesting that two or more cations accompanied the amino acid during transport. l-[3h]glutamate influx illustrated the following kinetic constants: apparent membrane binding affinity (kapp) = 0.80 +/- 0.12 mm; influx velocity (jmax) = 2.61 +/- 0.31 protein-1.min-1; and permeability coefficient (p) = 0.65 +/- 0.10 protein-1. mi ...19892568760
partial purification of parathyrin from the corpuscles of stannius (pcs) of the eel (anguilla anguilla, l.).it has been previously shown that the eel corpuscles of stannius (cs) synthesize and secrete a substance (pcs) which is functionally and immunologically related to the mammalian parathyrin family. purification of pcs, including anion-exchange chromatography, ods c-18 reverse-phase hplc, and affinity chromatography, showed that a biologically active peak, eluted in 32% acetonitrile, contains a 32- to 34-kda protein which is 600-fold more potent than the crude extract is a test involving the hypoc ...19892599351
effects of long-term exposure to hydrostatic pressure per se (101 ata) on eel metabolism.oxygen consumption, mo2, has been measured in yellow freshwater eels (anguilla anguilla l.) exposed in normoxic conditions for 31 days at a hydrostatic pressure of 101 ata (atmosphere absolute; 1 ata = 0.1 mpa) using a high pressure water circulation system. the results (series i) show that from a maximal value observed at the end of compression, mo2 decreases exponentially with time (tau congruent to 1.4 days) then reaches a steady state (mo2 = 0.67 +/- 0.05 at a lower level than ...19892611722
effects of vertebrate prolactins and growth hormones on thyroxine 5'-monodeiodination in the eel (anguilla anguilla): a potential bioassay for growth hormone.growth hormones (ghs) and prolactins (prls) purified from representatives of each vertebrate class from bony fish onwards were tested for their ability to stimulate in vivo peripheral deiodination of labeled thyroxine (t4*) into triiodo-l-thyronine (t3*) in the eel. plasma t3*/t4* ratio was used as parameter. all ghs significantly increased t3*/t4*, the magnitude of the response being unrelated to the phylogenic position of species. no significant stimulation was shown with the various prl, with ...19892707580
cupula displacement, hair bundle deflection, and physiological responses in the transparent semicircular canal of young eel.the transparent labyrinth of young eels (anguilla anguilla l.) was used in toto for studying the configuration of cupula displacement, deflection of the hair bundle, and correlated changes in transepithelial voltage (delta tev) and nerve activity (delta na) in the semicircular canal. microcapillaries were introduced into the canal through holes produced by a microthermocauter. mechanical stimulation was applied either by injection of fluid into the ampulla or by electromagnetically displacing fe ...19892740206
how many na+-dependent carriers for l-alanine and l-proline in the eel intestine? studies with brush-border membrane vesicles.using brush-border membrane (bbm) vesicles prepared from the intestine of the european eel, the specificity of l-alanine and l-proline na+-dependent transport was investigated by measuring the uptake of isotopically labelled substrates. in the presence of na+ ions, cross-inhibition between alanine and proline transports was observed; in addition alpha-(methylamino)isobutyric acid (meaib) inhibited proline but had no effect on alanine uptake. these results can be explained by the presence, in eel ...19892765548
isolation and primary structure of the c-peptide of proinsulin from the european eel (anguilla anguilla).1. the primary structure of the c-peptide of proinsulin from the european eel has been established as: dvepllgflspksgqenevddfpykgqgel. the peptide was isolated from the extract of eel pancreas in a yield that was approximately equimolar with insulin. a comparison with the predicted structures of c-peptides from other teleost fishes has identified a domain in the central region of the peptide that has been more highly conserved than the rest of the molecule.19892776429
brush-border amino acid transport mechanisms in carnivorous eel intestine.brush-border membrane vesicles (bbmv) were prepared from european eel (anguilla anguilla) intestinal epithelium by a magnesium-ethylene glycolbis(beta-aminoethyl ether)-n,n,n',n'-tetraacetic acid (egta) precipitation technique. amino acid transport by these purified vesicle preparations was investigated using either radiolabeled substrates or the voltage-sensitive fluorescent dye 3,3'-diethylthiadicarbocyanine iodide [disc2(5)]. all amino acids tested exhibited carrier-mediated, na+-dependent an ...20092782453
immunocytochemical analysis of the dopamine system in the brain and spinal cord of the european eel, anguilla anguilla.the distribution of dopamine-containing perikarya and fibres in the central nervous system of the eel, anguilla anguilla, was determined by using a specific dopamine antiserum. telencephalic dopamine-immunoreactive somata are located in the external cell layer of the olfactory bulb and throughout the rostrocaudal extent of the subpallium; immunoreactive fibres are located primarily in the bulb and in ventral and lateral portions of the hemispheres. diencephalic dopamine-immunoreactive neurons ar ...19892802190
triiodothyronine binding to putative solubilized nuclear thyroid hormone receptor in liver and gill of the brown trout (salmo trutta) and the european eel (anguilla anguilla).the binding of 3,5,3'-triiodothyronine (t3) to salt-extracted nuclear protein of liver and gill from trout and eel was studied in vitro. [125i]t3 binding depended on the temperature and protein concentration. binding equilibria were achieved in the two tissues of each species between 15 and 24 hr at 4 degrees. the binding was reversible in the presence of excess unlabeled t3. scatchard analysis showed a single class of high affinity and low capacity t3 binding species considered, 2.71 x 10(-10) ...19892806877
water and lactate movement in the swimbladder of the eel, anguilla anguilla.hemoglobin (hb) and lactate (la) concentrations were measured in small (150 microliters) blood samples collected with micropipettes from the inflow and outflow vessels of the rete mirabile of the eel swimbladder. hemoglobin was used as a marker of the intravascular space. 1. hemoglobin concentrations suggest that there was no significant water movement between the arterial and venous capillaries in the rete, but a significant 6% water efflux from the vascular space into the swimbladder epitheliu ...19892813987
temperature acclimation and oxygen binding properties of blood of the european eel, anguilla anguilla.temperature acclimation of the european eel, anguilla anguilla, resulted in red cell gtp/hb molar ratios of 1.20, 1.77 and 0.80 at 2, 17 and 29 degrees c, respectively. a small increase in blood oxygen capacity was present in 29 degrees c acclimated eels. the co2 bohr effect and the shape of the oxygen binding curve (n-hill) were invariant with both temperature and gtp/hb. the significant differences in the gtp/hb ratio corresponded with a strong enhancement of the temperature effect on blood ox ...20062859959
seasonal variations in hematocrit, red cell hemoglobin and nucleoside triphosphate concentrations, in the european eel anguilla anguilla.eels acclimatized in nature show a significant annual variation in erythrocytic guanosine triphosphate (gtp) concentration, temperature range 0.5-17 degrees c. a similar but smaller annual variation is also present in eels acclimated in the laboratory at constant temperature, 17 degrees c. hematocrit and blood oxygen capacity showed no seasonal variation. natural minimal and maximal red cell gtp concentrations were found at the end of the dormancy period (march) and in the late summer, respectiv ...19852859960
detection of endocrine cells by immunofluorescence method in the gastroenteropancreatic system of the adult eel, glass-eel, and leptocephalic larva (anguilla anguilla l.).five antisera against insulin (ins), glucagon (glu), somatostatin (srif), met-enkephalin (met-enk), and serotonin (5-ht) were used for immunofluorescence detection of endocrine cells in pancreas and gastrointestinal tract (git) of the european eel (anguilla anguilla l.) at three stages of development (leptocephalic larva, glass-eel, and adult eel). comparable distribution of endocrine cells was observed for adults and glass-eels. in their pancreatic islets, positive immunoreactions were obtained ...19852861142
suppression of plasma thyroid hormone concentrations by cortisol in the european eel anguilla anguilla.female european eels, anguilla anguilla, were given a single intra-arterial injection via a catheter of cortisol hemisuccinate at doses ranging from 3.5 to 35 micrograms (15 to 150 micrograms/kg body wt), yielding mean plasma cortisol levels of 87-410 ng/ml 2 hr after injection. cortisol treatment (17.5 and 35 micrograms) significantly decreased plasma levels of thyroxine (t4) and triiodothyronine (t3) within 24 hr relative to those in control fish. cortisol treatment (35 micrograms) appeared to ...19862870843
the relationship of eel anguilla anguilla (l.) body size, lipid, protein, glucose, ash, moisture composition and enzyme activity (aldolase).body composition: protein, lipid, ash, moisture; and enzyme activity (aldolase) were studied in european eels (anguilla anguilla) of various sizes. the fish were brought to the laboratory as glass eels (0.35 g) and maintained under controlled conditions (23 degrees c) for one year. after one year of growth, various sizes (between 9 and 420 g) were found. significant correlation coefficients of the equation w = a ln c + b (where w = body weight, in g; c = composition, % or activity, u; and a,b ar ...19862875842
effect of dietary carbohydrate source on soluble protein glucose concentration and enzyme activity (aldolase) of european eels (anguilla anguilla l.).this study was undertaken to determine the influence of dietary carbohydrate sources: wheat meal, bread meal, soluble corn starch, native potato starch and sorghum meal, on soluble protein, enzyme activity (aldolase) and glucose concentration in muscle and liver of european eels (anguilla anguilla). there was less soluble protein in both muscle and liver of eels fed 30% wheat meal or bread meal than the other experimental groups. however, eels fed 30% bread meal or soluble corn starch had a high ...19872886257
effects of hydrostatic pressure on the motor activity of fish from shallow water and 900 m depths; some results of challenger cruise 6b/85.1. two species of benthic fish from 900 m depths (90 atm pressure), trachyscorpia cristulata echinata and synaphobranchus kaupi, are shown to be adapted to their normal, high ambient pressure. 2. their condition improves when they are restored to their normal pressure after experiencing decompression in a trawl and they undergo convulsions at 150 atm. 3. this contrasts with the response of shallow water species (salmo salar, pleuronectes platessa, anguilla anguilla and gadus morhua) which convul ...19872892630
the effect of pressure on the lateral swimming muscle of the european eel anguilla anguilla and the deep sea eel histiobranchus bathybius; results of challenger cruise 6b/85.1. the viability of histiobranchus lateral muscle was prolonged up to 7 times by recompression of the tissue. 2. the maximum twitch contraction force of both anguilla and histiobranchus was recorded at a pressure between 150 and 350 atm. at 1 atm anguilla developed 60% maximum force and histiobranchus 10-20% maximum force. 3. twitch contraction time doubled for a pressure increase of 400 atm. this effect is predicted to halve the maximum swimming speed at 4000 m and is discussed in relation to m ...19872892634
somatostatin-related and glucagon-related peptides with unusual structural features from the european eel (anguilla anguilla).peptides derived from prosomatostatins i and ii and from two distinct proglucagons have been isolated from the pancreas of a teleost fish, the european eel (anguilla anguilla). the product of prosomatostatin i processing, somatostatin-14, is identical to mammalian somatostatin-14. a 25-amino-acid-residue peptide (ser-val-asp-asn-gln5-gln-gly-arg-glu-arg10-lys-ala-gly-cys- lys15-asn-phe-tyr- trp-lys20-gly-pro-thr-ser-cys25) is derived from prosomatostatin ii. compared with the corresponding pepti ...19882904391
properties of european eel (anguilla anguilla) liver cell sap acetyl-coa carboxylase. 20102905607
regulation of eel (anguilla anguilla) liver acetyl-coa carboxylase by changes in the polymeric state of the enzyme. 20102905608
basolateral amino acid and glucose transport by the intestine of the teleost, anguilla anguilla.1. d-glucose transport into blmv was osmotically reactive, sodium independent, and inhibited by phloretin but not by phloridzin. 2. the survey of 6 l-amino acids identified three groups with respect to transfer across the basolateral cell border. transport of proline and glutamate occurred by na-dependent carriers and by apparent simple diffusion. alanine, lysine and phenylalanine were transported by na-independent carriers and apparent simple diffusion. glycine transport was stimulated above ap ...19882907446
ventilatory and circulatory adjustments in the european eel (anguilla anguilla l.) exposed to short term hypoxia.respiratory and circulatory (measured and calculated) variables were obtained at the same time in resting eels, during normoxia and after 1 h exposure to environmental hypoxia (water po2 of 40 torr). in normoxia, values of respiratory and circulatory variables appeared less than those reported for most other fish. these differences could be partly explained by a lower level of standard metabolism and a greater uptake of o2 through the skin. hypoxia caused a marked decrease in heart rate (40%), c ...19892920810
brush-border inositol transport by intestines of carnivorous and herbivorous teleosts.transport characteristics of myoinositol by isolated brush-border membrane vesicles of two fish, the herbivorous tilapia (oreochromis mossambicus) and the carnivorous eel (anguilla anguilla), were measured. [3h]myoinositol uptake by vesicles of both fish was stimulated by a transmembrane na gradient, was electrogenic, and was inhibited by phloridzin. kinetic analysis of myoinositol influx disclosed species differences (tilapia, k = 0.15 mm, jmax = 0.2 protein-1.min-1; eel, k = 2.6 mm, jm ...19892923211
basolateral inositol transport by intestines of carnivorous and herbivorous teleosts.myoinositol transport by isolated basolateral membrane vesicles was characterized from intestines of the herbivorous tilapia (oreochromis mossambicus) and the carnivorous eel (anguilla anguilla). [3h]myoinositol transport occurred by nonelectrogenic, facilitated diffusion independent of cation gradients and was inhibited by phloretin (ki = 0.6 and 0.9 mm for tilapia and eel, respectively) but not by phloridzin. kinetic analysis of myoinositol influx disclosed no differences in concentration yiel ...19892923212
ionic and total calcium levels in the blood of the european eel (anguilla anguilla): effects of stanniectomy and hypocalcin replacement therapy.removal of the corpuscles of stannius (stx) in the freshwater european eel causes a marked increase in the concentrations of blood ionic calcium and protein-bound calcium. the hypercalcaemia peaks 20 days after stx and lasts at least another 20 days. in stanniectomized eels hypocalcin decreased both blood ionic and total calcium concentrations. the reduction of plasma total calcium concentration by hypocalcin is attributed to a reduction in blood ionic calcium concentration. we conclude that hyp ...19892926317
live and reactivated motility in the 9+0 flagellum of anguilla sperm.the sperm flagella of the eel, anguilla anguilla, are capable of vigorous motion in spite of having an axoneme with reduced structure that lacks the outer dynein arms, radial spokes and spoke heads, the two central tubules and the central tubule projections that are all part of the standard "9+2" axoneme. these sperm progress forward rapidly as a result of the propagation of helicoidal waves distally along the flagellum. their flagellar beat frequencies are high, 93 hz at 21 degrees c, and they ...19852931175
comparative aspects of circulating erythrocytes in the trophic and reproductive phases of european eel. ultrastructure and cytochemistry.different cytochemical and morphological parameters were used to compare the functional patterns of the erythrocytes in the transition from the trophic (yellow eel) to the reproductive (silver eel) phases of european eel (anguilla anguilla l.). data on the nucleus were obtained by microdensitometric (feulgen reaction) and cytofluoremetric (propidium iodide and hoechst 33342 fluorochromization) evaluations of dna staining intensity. in the silver eel, chromatin condensation was more heterogeneous ...19852935220
[accumulation of cyclic adenosine monophosphate in the ovary of the eel (anguilla anguilla l.) in vitro under the effect of carp gonadotropin or ovine lutropin: kinetics and thermodependence].cyclic amp (camp) in pieces of eel ovary was greatly increased in vitro by the gonadotropin (cgth) of carp, another teleost fish; after one hour at 20 degrees c, maximal stimulation = 31.7 and e.d. 50 = 0.08 micrograms/ml. ovine lutropin (olh) had less effect (maximal stimulation: 2.35; e.d. 50: 1.42 micrograms/ml); its action suggested that it involved a subfraction (olh/cgth rac) of the receptor-adenylate cyclase (rac) systems which mediate the action of cgth. another difference was the percen ...19863012723
[in vitro translation of rna extracted from corpuscules of stannius of the eel (anguilla anguilla); identification of the precursor of parathyrin in the corpuscules of stannius (pcs)].corpuscles of stannius (cs) of teleosts secrete a pth like hormone (parathyrin of cs: pcs) which is involved in calcium metabolism by acting mainly at the gill level. translated products encoded by mrna extracted from eel corpuscles of stannius and among these, translated products immunoprecipitated by anti b-pth immunserum were compared to the products synthetized during incubation of the glands with labelled methionine. the analysis was performed by polyacrylamide gel electrophoresis and fluor ...19873105830
capacity of the european eel (anguilla anguilla) to elongate and desaturate dietary linoleic acid.the ability of eels (anguilla anguilla) to further desaturate and chain elongate linoleic acid, 18:2n-6, was studied by feeding diets containing either corn oil or a fish oil to groups of elvers for 12 wk and analyzing proportions of fatty acids in tissue lipids. over the 12-wk period elvers given both dietary treatments increased in weight by fourfold. the proportion of arachidonic acid, 20:4n-6, present in polar lipids of elvers fed the diet containing corn oil increased from an initial value ...19873114442
detection of surface carbohydrates on pneumocystis carinii by fluorescein-conjugated lectins.lectins react with a wide range of different carbohydrates (table 1). even so-called monospecific anti-h(o) lectins from lotus tetragonolobus, ulex europaeus, and anguilla anguilla react not only with the anti-h determinant but also with several fucosylated carbohydrates. consequently, the type of lectin receptor existing on the surface of pneumocystis carinii should be determined, because only a carbohydrate analysis can demonstrate the kind of carbohydrates which exist on the cell surface of t ...19873125541
na-dependent l-proline transport by eel intestinal brush-border membrane vesicles.l-[3h]proline uptake by brush-border membrane vesicles prepared from intestinal mucosa of the european eel, anguilla anguilla, was stimulated by a transmembrane na gradient (out greater than in). kinetic analysis of l-proline influx, under short-circuited membrane potential conditions, indicated the presence of an apparent single na-dependent carrier process (kapp = 0.23 +/- 0.04 mm and jmax = 7.96 +/- 0.87 protein-1.min-1) and a nonsaturable transfer component with an apparent diffusion ...20113177696
retinal fine structure in the european eel anguilla anguilla. v. pigment epithelium of the sexually immature silver eel stage.the fine structure of the retinal pigment epithelium (rpe), bruch's membrane and choriocapillaris has been investigated in the sexually immature silver eel and compared with previous observations made at the glass and yellow eel stages of the lengthy life cycle of the european eel. as in the previous stages the retinal pigment epithelium of the sexually immature silver eel consists of a single layer of cuboidal to squamous cells joined laterally by apically located cell junctions. the basal (scl ...19883189826
retinal fine structure in the european eel anguilla anguilla. vi. photoreceptors of the sexually immature silver eel stage.this report deals with the fine structure of the photoreceptors of the sexually immature silver eel and compares these findings with previous observations on the glass and yellow eel stages of the life cycle of the european eel. the photoreceptors of the sexually immature glass eel are readily categorized as either rods or cones. no multiple cones are observed. the rod:cone ratio is about 100:1, which is greater than that of either the glass or yellow eel stages. rods and perhaps cones also are ...19883189834
retinal fine structure in the european eel anguilla anguilla. vii. pigment epithelium of the sexually mature silver eel stage.this report describes the morphology of the retinal pigment epithelium (rpe), bruch's membrane and choriocapillaris in the sexually mature silver eel and compares these observations with previous descriptions of this region in the glass, yellow and sexually immature silver eel stages of the lengthy life cycle of the european eel. the retinal epithelium in the sexually mature silver eel is a single layer of cuboidal to squamous cells joined laterally by apically located cell junctions. both the b ...19883189844
retinal fine structure in the european eel anguilla anguilla. viii. photoreceptors of the sexually mature silver eel stage.the morphology of the photoreceptors of the sexually mature silver eel has been investigated by electron microscopy and these findings compared with observations made on the photoreceptors of the glass, yellow and sexually immature silver eel stages of the lengthy life cycle of the european eel (anguilla anguilla). as in previous stages the photoreceptors of the sexually mature silver eel are adequately described as either rods or single cones. the rod: cone ratio at this stage is about 200: 1 w ...19883189854
the mechanical properties of polyneuronally innervated, myotomal muscle fibres isolated from a teleost fish (myoxocephalus scorpius).single or small bundles of fibres were isolated from the abdominal myotomes of the sculpin myoxocephalus scorpius, a teleost with a polyneuronal pattern of fast muscle innervation. fibres responded to a supra-threshold stimulus with an all-or-none twitch. tetanic fusion frequency at 3 degrees c was 40-60 hz, and the twitch tetanus ratio 0.70. maximum isometric tension was 281 kn m-2. similar isometric contractile properties were obtained from the focally innervated fast muscle fibres of another ...19883194174
a study of barosensitivity in the european eel (anguilla anguilla, l.): effects of arterial pressure changes on heart rate and ventilation.a study of the effects of arterial pressure changes on heart rate and ventilation was carried out on the eel (anguilla anguilla l.). the anatomical characteristics of this fish enabled extracorporeal circulation in both the ventral and dorsal aorta to be set up. the pressure was changed mechanically, either by clamping external circulations or, in some cases, by modifying the frequency of a pulsatory pump placed in series with the heart, thus ensuring constant blood flows in the ventral aorta. t ...19883220126
efficacy of fumagillin against myxidium giardi cépéde, 1906 infection of the european eel (anguilla anguilla): new observations on myxidiosis of imported glass eels. 19883254089
arginine vasotocin binding to isolated branchial cells of the eel: effect of salinity.binding of 125i-labelled arginine vasotocin (avt) was studied in isolated intact gill cells obtained from eels (anguilla anguilla) adapted to fresh water (fw) or to sea water (sw). experiments carried out at 20 degrees c showed maximum and stable binding beyond 10 min of incubation. specific binding, determined by using labelled peptide in the presence or absence of an excess of unlabelled hormone, represented 30-50% of total and was reversible, with a half-time of less than 5 min. scatchard plo ...19883255360
coexistence of corticotropin-releasing factor-like immunoreactivity and vasotocin in perikarya of the preoptic nucleus in the eel.a corticotropin-releasing factor (crf)-like system has been identified in eels (anguilla anguilla, a. rostrata, and a. japonica) with immunocytochemical techniques. immunoreactive perikarya were located in the preoptic area, in magno- and parvocellular regions of the preoptic nucleus. fine fibers reached the pituitary and terminated in the neurohypophysis close to the corticotropic cells of the rostral pars distalis and caudally close to the melanocorticotropic cells of the intermediate lobe. do ...20123286370
structural studies of nerve terminals containing melanin-concentrating hormone in the eel, anguilla anguilla.eels were adapted to black- or white-coloured backgrounds and the pituitary glands were prepared for light and electron microscopy. immunocytochemical staining was used to study the distribution of the neurohypophysial melanin-concentrating hormone in the neurointermediate lobe. the hormone was located in small, elliptical, electron-opaque neurosecretory granules, measuring approximately 120 x 90 nm. the neurones terminated on blood vessels in the centre of the neurohypophysis and on the basemen ...19883345554
identification of hypocalcin (teleocalcin) isolated from trout stannius corpuscles.we have isolated and purified a glycoprotein from the corpuscles of stannius (cs) of trout, which we consider hypocalcin (also called teleocalcin), the major hypocalcemic hormone of fish. this product is present in relatively large amounts in the cs of several species (i.e., european eel, tilapia, goldfish, and carp). hypocalcin is typically released from the cs in response to an experimentally induced increase of the blood calcium concentration. ultrastructural observations show that after this ...19883360288
a peptide from the eel pancreas with structural similarity to human pancreatic secretory trypsin inhibitor.the primary structure of a 61-amino-acid residue peptide from the pancreas of the european eel (anguilla anguilla) has been established as e e k s g(5)l y r k p(10)s c g e m(15)s a m h a(20)c p m n f(25)a p v c g(30)t d g n t(35)y p n e c(40)s l c f q(45)r q n t k(50)t d i l i(55)t k d d r(60)c. there was no indication of microheterogeneity. this peptide shows structural similarity to pancreatic secretory trypsin inhibitors from several mammalian species and to a cholecystokinin-releasing peptid ...19883371360
solubility of nitrogen and argon in eel whole blood and its relationship to ph.the solubility coefficients (alpha) for the inert gases, nitrogen (n2) and argon (ar), were measured by mass spectrometry in whole blood of the freshwater-adapted european eel, anguilla anguilla, at varied ph and at two temperatures, 5 and 15 degrees c. the ph was altered either by varying pco2 (0.75-75 mmhg; 1 mmhg = 133.3 pa) or by adding fixed acid (hcl or lactic acid). no dependence of alpha on ph (range 5.5-8.4) or on lactate concentration (range 0.2-25 mmol l-1) was detectable. average val ...19883373142
diel and seasonal rhythms of the heart rate in the common eel (anguilla anguilla l.): role of cardiac innervation.using a computerized system, ecg recordings of eels were made during long-term experiments, to show circadian and circannual variations in the heart rate. the circadian variations synchronize with the photoperiod. the maximum frequency is observed during the dark phase, the peak values occurring just after sunset and before sunrise. by using specific blockers--atropine, propranolol, desmethylimipramine--the respective roles of neurotransmitters (acetylcholine and catecholamines) were evaluated. ...19883384071
the nutrition of the gill parasitic monogenean pseudodactylogyrus anguillae.a histological and histochemical study of ingested food material, energy stores and enzymes in the monogenean pseudodactylogyrus anguillae, parasitizing the gills of the european eel (anguilla anguilla) is presented. it was found that mucus, epithelial cells and blood from the gills were ingested. glycogen deposits were small and primarily located in the parenchyma and to a minor extent in the vitellariae. numerous globules of neutral lipids were found in the vitellariae. a marked esterase activ ...19873422977
daniconema anguillae gen. et sp. n., a new nematode of a new family daniconematidae fam. n. parasitic in european eels.a new nematode genus and species, daniconema anguillae gen. et sp. n., is described from the serosa of the swimbladder and from the intestine of eels (anguilla anguilla (l.] from denmark (lake esrum, northern zealand); a new family daniconematidae fam. n. is established to accommodate it. the hitherto monotypic family daniconematidae shows affinities with the skrjabillanidae; in contrast to the latter, the new family is characterized by the absence of a buccal capsule, by the presence of anus in ...19873428765
co-localization and secretion of parathyrin of stannius corpuscles (immunoreactive parathyroid hormone) and of secretory glycoproteins including secretory protein-i in the european eel (anguilla anguilla l.).until recently, teleosts were considered to be devoid of parathyroids. we showed recently that the corpuscles of stannius, that structurally have features in common with the parathyroid gland, produce a molecule resembling mammalian parathyroid hormone (pth). we refer to this molecule as parathyrin of corpuscles of stannius (pcs). parathyroid secretory protein-i (sp-i) is an acidic glycoprotein, probably identical to adrenal chromogranin a, that is co-stored and co-secreted with pth. in the pres ...19873504727
parasitological study of a population of tiber river eels (anguilla anguilla).a study was conducted on the parasitofauna of anguilla anguilla caught in the section of the tiber river south of rome (italy). the sample examined consisted of 417 specimens that were classified by stage (elver, young yellow eel, yellow eel and silver eel) and season of sampling. the following species were identified: trypanosoma granulosum, eimeria anguillae, myxidium giardi, sphaerospora reichenowi, myxobolus sp., trichodina anguilli, ichthyohodo sp., gyrodactylus anguillae, bothriocephalus c ...19873508508
ovarian metabolic pathways of steroid biosynthesis in the european eel (anguilla anguilla l.) at the silver stage.ovarian slices of the european eel at the silver stage were incubated with 4 tritiated precursors (pregnenolone, progesterone, androstenedione, testosterone) in the presence or not of an inhibitor of 11 beta-hydroxylase activity, metopirone. ether extracts were submitted to a gradient elution chromatography on celite columns. isolated peaks were identified by isopolarity on tlc, microchemical reactions and recrystallization to constant specific activity. interpretation of the results shows that ...19863517503
activation of trout gill amp deaminase by an endogenous proteinase--iii. comparative studies on the gill amp deaminase from different fresh water and sea water teleosts.the effects of monovalent cations and inorganic phosphate, on gill amp deaminase, were compared in different fresh water and sea water stenohaline and euryhaline teleosts. generally, sea water species displayed a lower sensitivity to these effectors than fresh water species. during salinity changes, the sensitivity of gill amp deaminase to cations and phosphate were modified proportionally to the tolerance of a given species to variations of environmental salinity. in particular, these parameter ...19863533411
the effects of neurohypophysial hormones on the vascular resistance of the isolated perfused gill of the european eel, anguilla anguilla l.arginine vasotocin (avt) and oxytocin (oxy), in the dose range of 2 x 10(-13)-2 x 10(-8) mol, were found to be potent vasoconstrictors of the arterioarterial pathway of isolated perfused eel gills. avt was significantly (p less than 0.05) more potent than oxy, as indicated by the results of both dose- and concentration-response curves. isotocin (it) and arginine vasopressin (avp) were unable to elicit a vascular response at doses of up to 2 x 10(-8) mol. the arteriovenous component of branchial ...19863557080
the concept of specificity in the procercoid-copepod system: bothriocephalus claviceps (cestoda) a parasite of the eel (anguilla anguilla).this paper describes experimental work on parasite specificity in the copepod-procercoid system of bothriocephalus claviceps. two criteria were used to characterize five potential host species macrocyclops albidus, macrocyclops fuscus, eucyclops serrulatus, acanthocyclops robustus and macrocyclops viridis viridis. the first criterion involves susceptibility of the copepods to infection. the results show random or aggregative distributions and variable susceptibilities according to the species. w ...19873575289
plasma concentrations of ovarian steroids in the freshwater european silver eel (anguilla anguilla l.): effects of hypophysectomy and transfer to sea water.intact and hypophysectomized freshwater (fw) silver eels were transferred to tanks of fw or artificial sea water (sw; salinity = 0.60 osmol/l) which were simultaneously renewed twice a week. fish were killed 2 months after transfer and plasma was assayed for ovarian steroids. in all fish, 5 alpha-androstane-3 beta,17 beta-diol was present, while 5 alpha-dihydrotestosterone and 5 alpha-androstane-3 alpha,17 beta-diol were undetectable. in intact fw eels, plasma levels of testosterone, 5 alpha-and ...19873655616
induction of spermatogenesis and spermiation by a single injection of human chorionic gonadotropin in intact and hypophysectomized immature european eel (anguilla anguilla l.).intact and hypophysectomized male silver eels (anguilla anguilla) in fresh water received a single injection of human chorionic gonadotropin (hcg) (250 c) or solvent (0.15 m nacl). no effect of solvent was observed. spermatogonia proliferated in testis of hcg-treated intact or hypophysectomized eels. one month after the injection, primary and secondary spermatocytes were found. after 3 months, numerous spermatozoa were present. in hypophysectomized eels, hcg was also effective even though maturi ...19873666426
comparative studies on lipid metabolism in various salt transporting organs of the european eel (anguilla anguilla). mono-unsaturated phosphatidylethanolamine as a key substance.1. incorporation in vivo into tissue lipids of (1-14c)acetate added to the water in the incubation tank showed the same relative distribution pattern of 14c-activity among various phospholipids in the gills, the esophagus and the intestine, when the eel was incubated in sea-water; in fresh water this pattern was found only in the intestine, while both the gills and the esophagus showed a relative excess of 14c-label in phosphatidylethanolamine (pe). 2. similar studies with (32p)phosphate also sh ...19873677610
co-existence of congeneric species of acanthocephala: acanthocephalus lucii and a. anguillae in eels anguilla anguilla in ireland.a population of eels anguilla anguilla from lough derg, r. shannon, ireland, harbouring infections of both acanthocephalus lucii and a. anguillae was studied over three years. both parasite species had the same intermediate host and eels appeared to be the only definitive host for a. anguillae. throughout the whole period, a. lucii was the dominant parasite, was over-dispersed throughout the eel population and most frequently occurred as a single species infection. a. anguillae was far less comm ...19873696765
the relationship of saccular efferent neurons to the superior olive in the eel, anguilla the eel, horseradish peroxidase was applied to the saccular ramus of the eight nerve to label auditory efferent neurons and was injected into the torus semicircularis to identify the superior olive. efferent somata cluster close to the lateral lemniscus. the superior olive is also associated with the lateral lemniscus and is situated just rostral to and contiguous with the efferent population. efferent cells can be distinguished from superior olivary neurons because of their larger size and t ...19863725216
the ca++ permeability of the apical membrane in neuromast hair cells.the mechanosensitivity of eel (anguilla anguilla) neuromasts was measured by the impulse responses of single afferent nerve fibers to mechanical stimuli. it is dependent on the potential across the skin and on the ions in the water outside the apical membrane of the sensory cells. the mechanosensitivity decreases to zero when the skin is polarized by 10-100 mv cathodal dc (skin surface negative); it increases with increasing (10-60 mv) anodal dc and remains remarkably constant with higher polari ...19863735160
na-dependent d-glucose and l-alanine transport in eel intestinal brush border membrane vesicles.brush border membrane vesicles (bbmv) were prepared from eel (anguilla anguilla) intestine by a mg-ethylene-glycol-bis(beta-aminoethylether)-n,n'-tetraacetic acid precipitation technique; the bbmv were enriched 16, 12, and 13 times in leucine aminopeptidase, maltase, and alkaline phosphatase activities with respect to the starting mucosal scraping. d-[3h]glucose and l-[3h]alanine transport by these vesicles was studied by a rapid filtration technique. d-glucose uptake was stimulated by a transme ...19863752280
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