an 8-year study on the elimination of pcbs and other organochlorine compounds from eel (anguilla anguilla) under natural conditions. 199422176041
a new mannan-binding lectin from the serum of the eel (anguilla anguilla l.): isolation, characterization and comparison with the fucose-specific serum lectin.a new mannan-binding lectin (mbl) and a previously described fucose-binding lectin (fbl) have been isolated from serum of anguilla anguilla by affinity chromatography on a-peptone-sepharose in combination with electroelution (mbl) or affinity chromatography using alpha-l-fucose-agarose (fbl). mbl has a mol. wt of approximately 246,000 and is composed of identical subunits of approximately 24,000, two of each are always covalently linked. fbl has a mol. wt of about 121,000 and consists of four su ...19947953065
sterol and fatty acid composition of neutral lipids of paratenuisentis ambiguus and its host eel.the sterol composition of free sterol and steryl ester fractions of the fish parasite paratenuisentis ambiguus was determined. in addition, the fatty acid composition of various neutral lipid classes, i.e., wax esters, steryl esters, triacylglycerols and free fatty acids, as well as the composition of the 1-o-alkyl moieties of total ether glycerolipids of the parasite, were investigated. the results of these studies were compared with those obtained on the intestinal tract tissue of its host, th ...19948090063
sequence and regulation of european eel prolactin mrna.cdna clones encoding the european eel (anguilla anguilla l.) prolactin were isolated from a pituitary cdna library constructed in gamma gt10, using a rainbow trout prl cdna fragment as a probe. four different inserts were subcloned into the pgem 3z plasmid after pcr amplification. the 1082 bp-long nucleotide sequence revealed an open reading frame of 627 bp encoding a 24 amino acid-long signal peptide followed by a 185 amino acid-long mature protein. comparison studies showed 60-70% homology wit ...19947926267
in vitro dose-response study of the effect of cadmium on eel (anguilla anguilla) gill na+/k(+)-atpase activities.the effect of cadmium exposure was studied in vitro on the atpase activities of gill membrane microsomes from seawater- and freshwater-adapted eel (anguilla anguilla) using a microassay technique. the basal activity (mg(2+)-atpase) was decreased by 40 and 25%, respectively, in seawater and freshwater preparations for the highest concentrations tested (respectively, 4 and 2 microm). the na+/k(+)-atpase activity was estimated either by potassium stimulation or by ouabain inhibition. this enzyme ac ...19947523067
ion transport across the isolated intestinal mucosa of anguilla anguilla (pisces).the posterior intestine of freshwater-adapted anguilla anguilla has a serosa negative transepithelial potential difference (tpd), and a current corresponding to the flow of negative current towards serosa. the tpd and the short-circuit current (scc) were inhibited by na+ and k+ withdrawal, and cl- substitution or ba2+ addition inverts tpd and scc, suggesting a cl- and na+ current mucosa-serosa, a k(+)-cl- cotransport and a k+ channel in the mucosal side. the tpd and scc were inhibited by ouabain ...20147520383
developmental changes in the content of dopamine in the olfactory bulb of the european eel (anguilla anguilla).the concentrations of dopamine (da) and of its major metabolite, dihydroxyphenylacetic acid (dopac), were measured in discrete areas of the eel brain. to investigate the developmental changes in the content of da and dopac, the assays were performed in yellow eels (i.e. at the feeding stage) and silver eels (i.e. at the migratory stage). da and dopac were unevenly distributed in the eel brain. in yellow eels, the concentration of da was highest (16-19 pmol/mg protein) in the olfactory bulb (ob), ...19948084534
adrenergic control of swimbladder perfusion in the european eel anguilla anguilla.adrenergic control of swimbladder blood flow was analysed in blood-perfused preparations of the european eel as well as in situ by recording the changes in swimbladder blood flow and blood pressure following an injection of catecholamine into the dorsal artery. in blood-perfused swimbladder preparations, injection of the alpha-adrenergic agonist phenylephrine into the perfusion loop caused a marked dose-dependent increase in perfusion pressure at constant flow, while injection of the beta-agonis ...19947964385
uptake and clearance of diazinon in different tissues of the european eel (anguilla anguilla l.).acute toxicity effects of diazinon on european eel (anguilla anguilla) was examined using short-term exposures in static conditions. the lc50 values were 0.16, 0.11, 0.09 and 0.08 mg/l at 24, 48, 72 and 96 h exposure, respectively. in addition, the eels were exposed to 0.042 mg/l of diazinon and bioaccumulation and clearance processes of this insecticide in liver, muscle and gill tissues were studied. bioconcentration factor (bcf) of diazinon over 96 h exposure period was 1850 in liver, 875 in g ...19948024718
somatostatin-related peptides isolated from the eel gut: effects on ion and water absorption across the intestine of the seawater eel.four somatostatin-related peptides were isolated from eel guts. two of them were the same as eel ss-25ii (ess-25ii) and eel ss-25i (ess-25i) isolated from european eel pancreas. the remaining two peptides were c-terminal tetradecapeptides (ess-14ii and ess-14i) of ess-25ii and ess-25i, respectively. these four peptides all enhanced the serosa-negative transepithelial potential difference and short-circuit current across the seawater eel intestine after pretreatment with isobutylmethylxanthine, s ...19947525832
rapid and simultaneous measurement of anodic and cathodic haemoglobins and atp and gtp concentrations in minute quantities of fish bloodoxygen transport to vertebrate tissues is dependent upon (a) the intrinsic o2-binding properties of haemoglobin (hb) and (b) modulation by allosteric effectors, such as nucleoside triphosphates (ntp), that depress hb o2-affinity in fish red cells. while some species, such as flatfish, primarily use adenosine triphosphate (atp) to modulate o2-binding to hb, others, such as eel and carp, also use guanosine triphosphate (gtp) (kono and hashimoto, 1977; leray, 1982; weber and jensen, 1988). unlike m ...19949317794
ion transport in the intestine of anguilla anguilla: gradients and translocatorsthe transport of na+, k+ and cl- across the isolated epithelium of the eel intestine was studied using a combination of four experimental strategies: short-circuiting, measurements of intracellular potentials and ion concentrations, application of a variety of transport inhibitors and measurement of unidirectional fluxes with radioactive tracers. when short-circuited, the system performs a net transport of cl- and na+ towards the blood side, with a stoichiometry approaching 2, and a much smaller ...19949317418
induction of g-bands on anguilla anguilla chromosomes by the restriction endonucleases haeiii, hinfi, and msei.fixed metaphase chromosomes of the eel anguilla anguilla were treated with the restriction enzymes haeiii, hinfi, and msei. all three restriction endonucleases are capable of inducing a g-band-like pattern if the incubation time and enzyme concentration are controlled. the results are discussed in relation to the main factors involved in the appearance of serial g-bands. chromatin organization, rather than dna composition, seems to account for the interstitial g-band pattern exhibited by these e ...19948404070
the distribution of gaba-immunoreactive neurons in the brain of the silver eel (anguilla anguilla l.).the distribution of gaba-immunoreactivity was studied in the brain of the silver eel (anguilla anguilla) by means of antibodies directed against gaba. immunoreactive neuronal somata were distributed throughout the brain. positive perikarya were detected in the internal cellular layer of the olfactory bulb, and in all divisions of the telencephalon, the highest density being observed along the midline. numerous gaba-reactive cell bodies were found in the diencephalon, particularly in the preoptic ...19948192235
the size and number of neurons descending to the spinal cord in relation to body length in the european eel (anguilla anguilla).cells of origin of descending spinal pathways in eels of different body lengths (15-59 cm) were identified by labelling them retrogradely with horseradish peroxidase from the rostral spinal cord. the aim was to determine whether changes in size, number and distribution of these neurons take place in line with changes in the size of the spinal targets that occur with increasing body length. the somal cross-sectional areas of the labelled cells were measured from horizontal frozen sections and cou ...19948082024
the branching of insulin-like growth factor 1 and insulin: an immunohistochemical analysis during phylogeny.the co-existence of insulin-like growth factor 1 (igf-1) with the classical islet hormones insulin (ins), glucagon (gluc), somatostatin (som) and pancreatic polypeptide (pp) in the endocrine pancreas of representative species of cyclostomes (myxine glutinosa), cartilaginous fish (raja clavata, squalus acanthias) and bony fish (cottus scorpius, carassius auratus, cyprinus carpio, anguilla anguilla) was studied by the use of monoclonal and polyclonal antisera and the double immunofluorescence tech ...19938265818
effect of lipid content of diet on cholesterol content and cholesterogenic enzymes of european eel liver.the effect of dietary lipid levels on the levels of cholesterol and the activities of the major cholesterogenic enzymes of the liver has been studied in the european eel. an increase in hepatic total cholesterol was observed when the dietary lipid levels increased from 12 to 20%, while protein levels were maintained at 30%. this change paralleled an increase in mevalonate 5-pyrophosphate decarboxylase activity, while 3-hydroxy-3-methylglutaryl-coa reductase mevalonate kinase and mevalonate 5-pho ...19938246691
importance of eating habits and sample size in the estimation of environmental mercury contamination using biological indicators.the importance of eating habits and the number of fish sampled in the estimation of mercury environmental contamination through biological indicators was studied. the species used were one with piscivorous habits (anguilla anguilla) and another with omnivorous habits (ciprinus carpio). from one original sample for each species, randomized samples were generated using the subroutine ggsrs from the mathematics library imsl, and later the statistical significance of pearson's correlation coefficien ...199324221024
synthesis of vitellogenin by eel (anguilla anguilla l.) hepatocytes in primary culture: requirement of 17 beta-estradiol-priming.control and 17 beta-estradiol-primed eels were used to investigate the hormonal requirement of vitellogenesis in an immature fish, the eel. a primary culture of isolated liver cells from female silver eels was developed. the hepatocytes were maintained as monolayers on poly-l-lysine coated dishes for up to 12 days in a defined medium alone or supplemented with 17 beta-estradiol (e2, from 10(-8) to 10(-5) m). the amounts of vitellogenin (vg) in the cells and secreted into the medium were measured ...19938224775
[cloning and sequence of thyrotropin beta subunit of a teleost fish: the eel (anguilla anguilla l.)].we obtained the sequence of eel thyrotropin beta-subunit cdna. about 1,100 bp long, it encodes a 147-amino acid protein including a 20-residue signal peptide. we analyse homologies between angtsh beta and the other known beta-subunits taking in account the ability of mammal gonadotropins (gth) to stimulate teleost thyroid. a peptide corresponding to mammalian cagyc (implicated in subunit association) is original and different from its eel beta gth2 counterpart.19938044698
differential distribution and response to experimental sexual maturation of two forms of brain gonadotropin-releasing hormone (gnrh) in the european eel, anguilla anguilla.using specific radioimmunoassays for the two gnrh molecular forms present in the european eel, anguilla anguilla, (mgnrh and cgnrh ii), we compared their distributions in the pituitary and different parts of the brain of female silver eels, as well as the modifications of their levels in experimentally matured female eels (treated with carp pituitary extract). in control eels, mgnrh levels were higher than cgnrh ii levels in the pituitary, olfactory lobes and telencephalon, di- and mesencephalon ...199324202465
ascorbic acid transport by intestinal brush-border membrane vesicles of the teleost anguilla anguilla.transport of l-ascorbate by intestinal brush-border membrane vesicles of european eel anguilla anguilla was stimulated by a transmembrane na gradient (out > in) but not by a similarly directed gradient of k. under short-circuited membrane potential conditions, a kinetic analysis of l-ascorbate influx indicated the presence of a single na-dependent carrier process (kapp = 0.75 +/- 0.07 mm and jmax = 0.33 +/- 0.03 protein-1.min-1) and a nonsaturable transfer component with an apparent diff ...19938322981
ultrastructural data on the sporogenesis of myxidium giardi, cépède 1906 (myxozoa, myxosporidia), parasite of anguilla anguilla (teleostea).ultrastructural study of myxidium giardi showed that pluricellularity is maintained by the formation of septate desmosomes. the polar capsule is formed from helicoidal depositions of banded material in the initial vacuole. this process makes possible not only the formation of the rigid capsular body but also of the flexible polar filament which is evaginable and reversed in the capsule. the special feature of the genus myxidium is the ornamentation of the valvogenic cells of the spores in the fo ...199323195549
stanniocalcin kinetics in freshwater and seawater european eel (anguilla anguilla).the kinetics and hypocalcemic potency of stanniocalcin (stc) were examined in freshwater and seawater eels. the secretion rate and the metabolic clearance rate of stc were calculated from the stc disappearance curve after intra-arterial injection of trout stc. basal plasma stc concentrations in freshwater and seawater eels did not differ but the stc secretion rate and metabolic clearance rate in seawater eel were 70-75% higher than in fw eel. the increased stc distribution space in seawater eels ...199324214449
peptide hormone-stimulated second messenger production in the teleostean nephron.renal actions of arginine vasotocin (avt) and atrial natriuretic peptide (anp) in teleosts are poorly defined. administration of these hormones changes renal function, largely explained by systemic vascular effects. the present experiments examine the potential direct action of these hormones on the teleost nephron. this has been assessed from the hormones' abilities to stimulate their second messenger systems within isolated nephroi of the rainbow trout onchorhynchus mykiss. following initial e ...19938392960
influence of protein/lipid ratio of diet on cholesterol synthesis and esterification in eel liver.the effect of protein/lipid ratio of diets on hepatic cholesterol has been studied in european eel and correlated with changes in the main enzymes responsible for cholesterol metabolism. the growth rates of animals were similar when dietary lipid level was 12%. however, a 25% protein/20% fat (25/20) diet produced a decrease in the weight gain when compared with that observed after feeding a 30/20 diet. at low fat level (12%), the decrease in dietary protein produced a little but significant incr ...20137684279
effect of insulin in the diet on the growth of european eels (anguilla anguilla l.).the effect of oral administration of insulin, in various concentrations, on the growth of european eels (anguilla anguilla l.) was studied. in order to determine whether the insulin penetrated through the stomach or gills to the blood system, 5 ml insulin, suspended in an 0.6% solution of nacl, was inserted via the mouth of eels, and the insulin content in the blood measured by radioimmunoassay immediately, and at one and two hours after administration. a control group was given 0.6% nacl alone. ...199224214275
h+/glycyl-glycine cotransport in eel intestinal brush-border membrane vesicles: studies with the ph-sensitive dye acridine orange.monitoring the fluorescence quenching of the ph-sensitive dye acridine orange, proton accumulation in the presence of an inside-negative transmembrane potential was measured in eel (anguilla anguilla) intestinal brush-border membrane vesicles. it was demonstrated that the proton accumulation was specifically increased by the presence of the dipeptide glycyl-glycine in the extravesicular space, showing saturation kinetics at increasing dipeptide concentrations and was specifically inhibited by di ...19921327139
the use of texture analysis for the discrimination of nissl substance in neurons.structural changes induced by cordotomy in the nissl substance of identifiable spinal motoneurons innervating the white musculature of the european eel were quantified with the use of texture features calculated from digitized images. data were evaluated and the motoneurons classified by using multivariate analysis. the study shows that there are differences in the structural organization of the nissl substance of motoneurons taken from control and cordotomized fishes. distinction could only be ...19921282188
chlorinated hydrocarbons in eels (anguilla anguilla l.) from the river rhine. 19921522922
effects of ambient ion concentrations on gill atpases in fresh water eel,anguilla anguilla.branchial activities of na(+),k(+)-atpase (ouabain sensitive), mg(2+) atpase (ouabain insensitive) and kinetic analysis of high and low affinity ca(2+) atpase were measured inanguilla anguilla that had been acclimated to demineralized water (dw, ca < 10 μm), freshwater (fw, ca = 2 mm), and low calcium freshwater (l-ca, ca = 0.9 mm). na(+),k(+)-atpase activity decreased while ouabain insensitive activity increased when ambient ca(2+) decreased. two kinetic forms of ca(2+) atpase could be resolved ...199224214197
acute toxicity, uptake and clearance of diazinon by the european eel, anguilla anguilla (l.).the toxicity, accumulation, and elimination of diazinon were investigated for the european eel, anguilla anguilla. the 24, 48, 72 and 96-h median lethal concentrations (lc50) were 0.16, 0.11, 0.09 and 0.08 mg/l, respectively. fish exposed to sublethal concentration (0.042 mg/l) accumulated diazinon in liver and muscle tissues. bioconcentration factors (bcf) of diazinon were 1850 in liver, and 775 in muscle over the 96-h exposure period. upon removal from diazinon containing water the contaminate ...19921593096
lindane-induced changes in carbohydrate metabolism in anguilla anguilla.1. anguilla anguilla (l.) was exposed to a sublethal concentration of 0.167 ppm (0.25 of the 96-hr lc50) of lindane for 6, 12, 24, 48, 72 and 96 hr. 2. changes in glycogen, glucose, pyruvate and lactate contents of liver and muscle after lindane exposure, were studied. 3. muscle and liver glycogen levels decreased significantly during the exposure time. muscle glucose values increased but on the other hand we found a decrease in those of liver. 4. muscle and liver pyruvate content increased as d ...19921379899
age-related decrease in the density of benzodiazepine recognition sites in the brain of the fresh water eel (anguilla anguilla).the binding parameters of benzodiazepine receptors labeled with [3h]flunitrazepam were investigated in the brain of male adult eels at the trophic phase (4 years old) and of male silver eels (6 year old ocean migrants). the density of [3h]flunitrazepam binding sites was significantly decreased (-26%) in the brain of silver eels compared with younger counterparts. in contrast, the apparent dissociation constant (kd) was not significantly different in the two experimental groups. these results are ...19911667812
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
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
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
changes in selected biochemical parameters in the brain of the fish, anguilla anguilla (l.), exposed to lindane. 19911722731
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
comparative study of acetylcholine synthesis in organs of freshwater teleosts.the activity of acetylcholine (ach) synthesizing enzyme, choline acetyltransferase (chat), and the content of ach were determined in the brain, heart, red trunk muscle and midgut of 12 freshwater teleost species belonging to eight families: carp (cyprinus carpio), tench (tinca tinca), silver carp (hypophthalmichtys molitrix), bighead (hypophthalmichtys nobilis), wels (silurus glanis), cat fish (ictalurus nebulosus), eel (anguilla anguilla), rainbow trout (oncorhynchus mykiss), pike (esox lucius) ...199124214667
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
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
effects of vasoactive intestinal polypeptide, substance p, 5-hydroxytryptamine, met-enkephalin and neurotensin on the swimbladder smooth muscle of two teleost species,gadus morhua andanguilla anguilla.the effects of vasoactive intestinal polypeptide (vip), substance p (sp), 5-hydroxytryptamine (5-ht), neurotensin (nt) and met-enkephalin (menk) on the smooth muscles of the teleost swimbladder were studied in two teleost species, the atlantic cod (gadus morhua) and the eel (anguilla anguilla). the study was made on isolated strip preparations of the muscularis mucosae, using putative transmitters corresponding to the immunoreactive materials that have previously been localized by immunohistoche ...199124214612
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
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
comparative acute toxicities of selected pesticides to anguilla anguilla.the acute toxicities (24, 48, 72 and 96 hr) of eight pesticides to anguilla anguilla were determined. the organochlorine pesticide, endosulfan was the most toxic, with lc50 values in the range of 0.042 to 0.041 mg/l. endosulfan was followed in order of decreasing toxicity by diazinon, fenitrothion, chlorpyrifos, lindane, methidathion, trichlorfon and methylparathion. when fishes were exposed to the pesticides tested they exhibited signs of restlessness, erratic swimming, convulsions and difficul ...19911723417
the effect of time on physiological changes in eel anguilla anguilla, induced by lindane.1. eel were exposed to a sublethal concentration of lindane (0.335 ppm) for 6, 12, 24, 48, 72 and 96 hr. 2. concentrations of glycogen, glucose, lactate, pyruvate and lipids were determined in gill tissue after lindane exposure. 3. gill glycogen decreased and glucose levels increased at 6 hr of treatment, lactate and pyruvate concentration increased between 6 and 48 hr. total lipid values decreased between 6 and 24 hr; thereafter, the levels increased up to 72 hr of exposure. 4. clear changes we ...19911713818
significant year-to-year variation of the response to radiation-induced stress shown by gill fatty acid metabolism in eels (anguilla anguilla) captured from the wild.1. in eels captured in roskilde fjord in 1972 and 1975, a specifically enhanced synthesis was found from 14c-acetate of 14c-labelled mono-unsaturated fatty acids (c16:1 and c18:1) relative to saturated fatty acids (c16:0 and c18:0) in sea water 4 days after irradiation (10 gy, 60co). 2. corresponding experiments in 1976 and 1982 showed rather the opposite: irradiation resulted in more 14c-labelled saturated fatty acids relative to unsaturated fatty acids, both in fresh and sea water. 3. the latt ...19911677881
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
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
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
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
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
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
[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
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
influence of fatty acid composition of diet on cholesterol content of eel liver and muscle.the influence of different diets on cholesterol content of liver and muscle of european eel (anguilla anguilla) was studied for the first time. in control eel, cholesterol constituted near 7.5% of total lipids in liver and about 1% in muscle. feeding herring meal-55% diet produced a drastic increase in hepatic cholesterol after a 30 d period. in muscle, cholesterol content also increased after any dietary treatment. free cholesterol represented about 34% of total cholesterol in liver and about 5 ...19901692683
[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
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
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
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
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
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
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
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
the gnrh systems in the brain and pituitary of normal and hcg treated european silver eels.the distribution of immunoreactive gnrh was studied in the brain and pituitary gland of normal and human chorionic gonadotrophin (hcg) injected silver eels. it was found that the general organization of gnrh systems in this species is similar to that reported in other teleosts. cell bodies were present in the olfactory bulbs, ventral telencephalon, periventricular hypothalamus and dorsal tegmentum. no positive perikarya could be detected in the preoptic region. only scarce fibers were observed i ...198924221596
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
positive feedback control by the gonads on gonadotropin (gth) and gonadoliberin (gnrh) levels in experimentally matured female silver eels,anguilla anguilla.treatment of sham-operated female silver eels with carp pituitary extract stimulated ovarian development and induced increases in pituitary gonadotropin (gth) and gonadoliberin (gnrh) contents. both effects of carp pituitary extract were abolished in ovariectomized eels, indicating the involvement of the gonads. endogenous sexual steroids, the secretion of which was increased during sexual maturation, should be responsible for the stimulation of gth and gnrh levels. ovariectomy itself had no sig ...198924221767
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
efficacy of fumagillin against myxidium giardi cépéde, 1906 infection of the european eel (anguilla anguilla): new observations on myxidiosis of imported glass eels. 19883254089
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
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
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. 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. 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
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
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
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
acute toxicity of organochlorined pesticides to the european eel, anguilla anguilla: the dependency on exposure time and temperature. 19872444293
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
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
[demonstration of specific binding sites for carp gonadotropin in ovary membrane preparations of anguilla (anguilla anguilla l.)].membrane preparations from silver eel ovary bind specifically labeled carp gonadotropin (cgth 125i); similar preparations from kidney, liver, brain, and muscle exhibit either no or negligible specific binding. cgth and partially purified eel pituitary extract, but neither hcg nor btsh, inhibit cgth 125i specific binding in a dose-dependent way. however, a high membrane concentration can bind hcg 125i and this binding is partly inhibited by excess hcg, thus suggesting the existence of a relativel ...19873817443
testis cytological structure, plasma sex steroids, and gonad cytosol free steroid receptors of heterologous gonadotropin (hcg)-stimulated silver eel, anguilla anguilla l.complete testicular maturation was induced in silver eels, kept at 24 degrees in fresh water, by a single injection of 1000 i.u. of heterologous gonadotropin (hcg). each week, for 4 weeks, some eels were examined for testis structural pattern, plasma sex steroids, and gonad cytosol steroid receptors. the first effect of the hcg was on the tubular organization of the testis, followed by spermatogenesis. plasma androgens were not detectable in the untreated eels, whereas a peak was detected a week ...19873817439
melanin concentrating hormone inhibits the release of alpha msh from teleost pituitary glands.a radioimmunoassay was developed for salmonid melanin concentrating hormone (mch) and used to measure immunoreactive (ir)mch in the hypothalamus and pituitary of trout (salmo gairdneri) and eels, (anguilla anguilla) maintained under different regimes of background color. in trout, 95% of the total irmch was located in the pituitary gland. the amount of mch in both pituitary and hypothalamus was increased when white-adapted trout were transferred to a black background. in eels, a similar change o ...19873803904
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
[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
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