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the attachment of the monogenean diplectanum aequans (wagener) diesing to the gills of morone labrax l. 19665968798
increase of (na+ plus k+)-dependent atpase activity in gills and kidneys of two euryhaline marine teleosts, crenimugil labrosus (risso, 1826) and dicentrarchus labrax (linnaeus, 1758), during adaptation to fresh water. 19714253146
[digestive proteases in a carnivorous teleost, dicentrarchus labrax]. 19744617533
[the origin of the locomotor and trophic activities in the young wolf-fish dicentrarchus labrax (l.) (pisces perranidae)].the spontaneous activities of a fixed type shown by the larvae of d. l. are at the beginning random (at least apparently) and not directed. the rheotactism which appears as soon as the eyes are pigmented has been used for the presentation of lures, thus allowing the study of the stimuli releasing the feeding activity and the breeding of 913 individuals up to the alevin stage.1975808350
[gill repartition of two monogenea: diplectanum aequans (wagener 1857), diesing 1958 and d. laubieri lambert and maillard 1974 (monogenea, monopisthocotylea) simultaneous parasites of the sea bass dicentrarchus labrax (author's transl)].the close observation of the gill habitat of two monogeneans diplectanum aequans (wagener 1857) diesing 1858 and diplectanum laubieri lambert and maillard 1974 shows the microbiotopes of these two simultaneous parasites of the sea-bass: dicentrarchus labrax. the authors propose to study the distribution of the monogeneans with references to three theoretic axes in the gill chambers. for the diplectanum, the populations spread on each of these axes according to preferential gradients.19751227377
[phyletic affinities among polystomatidae (monogenea)].the chaetotaxy and ciliated cells in two monogenean larvae of marine fishes are described for the first time: a monopisthocotylea diplectanum aequans (wagener, 1857) diesing, 1858 parasite of dicentrarchus labrax (l) and a polyopisthocotylea, microcotyle mormyri lorenz, 1878 parasite of pagellus mormyrus (l). a comparative study with the known larvae shows evidence of two larval types in the monogenea of fishes, related to the two great phyla of the class: the monopisthocoytylea and polyopisthoc ...1977413661
[arrhenius diagrams of respiratory enzymes of liver mitochondria from bass (morone labrax)].arrhenius plot of glutamate, succinate and ascorbate+tmpd oxidation in bass liver mitochondria show a break at different temperatures. above the break activation energies (ea) of the three enzymes. above the break activation energies (ea) of the three enzymes examined are similar and comparable with literature data in poikilotermic and homeothermic animals. below the break the ea are again comparable with poikiloterm and homeotherm ones except for succinate-oxidase whose ea is surprisingly highe ...19826131679
[respiration and oxidative phosphorylation in liver mitochondria of bass (morone labrax) and their dependence on temperature].in the present paper the respiratory function in bass liver mitochondria is studied over the temperature range 6-34 degrees c. the respiratory rate in state 3 and state 4 at the temperatures examined agrees with data from poikiloterms reported elsewhere by other investigators icr and adp/o values with glutamate and succinate as substrates are considered and their variations as a function of the experimental temperature are discussed. icr shows a maximum at 20 degrees c which approximatively corr ...19826131678
effects of hypoxia on blood gas and acid-base parameters of sea bass.continuous recordings have been made of ph, po2, and pco2 of arterial blood (pha, pao2, paco2) in an extracorporeal circulation during periods of hypoxia (inspired po2 45-10 torr) in sea bass, morone labrax. during moderate hypoxia hyperventilation was accompanied by an increase in pha. continuation of moderate hypoxia for periods up to 24 h produces an increase in lactate and a consequent decrease in pha. during deep hypoxia there is a very brief alkalosis as ventilation increases but a marked ...19826818206
analysis of two chloride requirements for sodium-dependent amino acid and glucose transport by intestinal brush-border membrane vesicles of fish.intestinal brush border vesicles of a mediterranean sea fish (dicentrarchus labrax) were prepared using the ca2+-sedimentation method. the transport of glucose, glycine and 2-aminoisobutyric acid is energized by an na+ gradient (out greater than in). in addition, amino acid uptake requires cl- in the extravesicular medium (2-aminoisobutyric acid more than glycine). this na+- and cl--dependent uptake is electrogenic, since it can be stimulated by negative charges inside the vesicles. the specific ...19836830788
effects of adaptation to different salinities on the lipids of various tissues in sea dace (dicentrarchus labrax pisces).1. effects of adaptation to four salinities (4, 18, 36 and 40 per 1000) have been studied in the main lipidic constituents (triglycerides, phospholipids, free fatty acids, cholesterol, triglyceride fatty acids) of the liver, muscle and intestinal tissue of dicentrarchus labrax--a euryhaline fish. 2. the study has been undertaken in spring, at a constant temperature of 13 degrees c after an adaptation of one month in the experimental reserve, with unchanged industrial food. 3. salinities 40, 36 a ...19836831868
[demonstration of natural killer cells (nk) in the breeding perch (dicentrarchus labrax). effect of breeding temperature]. 19836825421
[cymothoadian parasitosis of the sea-dace (dicentrarchus labrax linnaeus 1758) during breeding. ii. parasitic ecophysiology in the diana pond (upper corsica)].this study deals with the problem of some aspects of the influence of infestation by an hematophagous parasite nerocila orbignyi (crustacean, isopoda, cymothoidae) on sea-bass (dicentrarchus labrax, l. 1758) ecophysiology, reared in the pond diana (corsica). we can summarise results as: decrease in body condition, in weight, in levels blood protein, blood lipids and triglycerides; but increase in levels blood urea. we too observe hypochromic macrocytic anemia with increase in eosinophils, neutro ...19836673645
[gonadal ontogenesis and sex differentiation in the sea bass, dicentrarchus labrax, under fish-farming conditions].the histology of the different stages of gonadal development (appearance of pgc, edification of gonad primordium, organization of an undifferentiated gonad, testicular or ovarian development) has been studied in fingerlings and juveniles of sea-bass in fish-culture conditions. sex differentiation with a caudo-cranial gradient was direct and more in accordance with length than with age. ovarian and testicular differentiation occurred in fish 11 to 23 months old and from 90 to 187 mm sl. testis ov ...19836844709
[life cycle of leranthropus kroyeri van beneden 1851, hematophagous branchial copepod of the sea bass dicentrarchus labrax (linné, 1758) in wild and experimental populations].the life cycle of lernanthropus kroyeri van beneden, 1851, copepod (siphonostomatoida) parasite of dicentrarchus labrax is described. the cycle comprises two nauplii, one infective copepodid, four fixed copepodids and one preadult. all the attached stages are caracterised by the lack of the frontal filament. this is the first description of a life cycle lacking a chalimus for siphonostomatoida copepods parasitic on fish.19846721378
daily rhythms of insulin and glucose levels in the plasma of sea bass dicentrarchus labrax after experimental feeding.significant and inverse circadian rhythms are demonstrated in glucose and plasma insulin in fish fed a natural diet. the highest glucose levels are found during the light period, around feeding time, and the insulin level peaks during the dark period. as a possible cause for the insulin rhythmicity, the daily variations in several plasma amino acids are considered. the feeding times could be a training factor for metabolic rhythms, which are maintained even during a fast of 7 days. the differenc ...19846381225
[first observations on the effect of various dietary oils on liver fatty acids in bass (dicentrarchus labrax)].a close relationship between dietary oils and fatty acid composition of bass liver and liver microsomes and mitochondria is reported in the present paper. among the data the most relevant is the evidence for elongation and desaturation of dietary 18:3 n-3 and 18:2 n-6, giving as a result an increase of 22:6 n-3 and 20:4 n-6 levels respectively. the importance of such findings in carnivore marine fish is discussed and compared with literature data.19846704237
[na+-atpase in the gills of bass (dicentrarchus labrax)].the authors evidence a mg2+ dependent atpase activity stimulated by na+ in absence of k+ in bass gill microsomes. as this stimulated atpase shows different features from "baseline" activity measured in the absence of both na+ and k+ ions (mg2+-atpase) and from 1mm ouabain sensitive (na+ + k+)-atpase, it has been ascribed to a distinct na+-atpase. in the present paper the optimal conditions for bass gill na+-atpase assay and the temperature dependence of the enzyme are reported. moreover the na+- ...19846142720
regulation of liver sea bass pyruvate kinase by temperature, substrates and some metabolic effectors.pyruvate kinase of sea bass (dicentrarchus labrax l.) shows positive cooperativity with respect to both substrates pep and adp. the temperature is a modulator of this activity, changing ks0.5 and hill coefficient values for pep. the enzyme shows alanine and atp inhibition and f-1,6-p2 activation at 22 degrees c. f-1,6-p2 eliminates the effect of alanine but not that of atp. these results could indicate a regulation of this enzyme by temperature and possess kinetic properties which are similar to ...19854092442
properties and function of malate enzyme from dicentrarchus labrax l. liver.malate enzyme (l-malate:nadp+ oxidoreductase (oxaloacetate decarboxylating, ec 1.1.1.40) has been purified from dicentrarchus labrax liver to 99% homogeneity by gel filtration, anion exchange and affinity chromatographies. the apparent molecular weight was estimated by gel filtration chromatography to be 148,000. analysis of the enzyme on sodium dodecyl sulphate polyacrylamide disc gel electrophoresis was shown to be a tetrameric protein. the purified enzyme showed a ph optimum 8.5 (tris-hcl buf ...19853967488
characterization of gill (na+ + k+)-atpase in the sea bass (dicentrarchus labrax l.).bass gill microsomal preparations contain both a na+, k+ and mg2+-dependent atpase, which is completely inhibited by 10(-3)m ouabain and 10(-2)m ca2+, and also a ouabain insensitive atp-ase activity in the presence of both mg2+ and na+. under the optimal conditions of ph 6.5, 100 mm na+, 20 mm k+, 5 mm atp and 5 mm mg2+, (na+ + k+)-atpase activity at 30 degrees c is 15.6 mumole pi hr/mg protein. bass gill (na+ + k+)-atpase is similar to other (na+ + k+)-atpases with respect to the sensitivity to ...19852981655
influence of atp and magnesium on phosphofructokinase from sea bass (dicentrarchus labrax l.) liver.glycolytic enzyme phosphofructokinase (pfk) from sea-bass liver shows inhibition for atp4- and mg-atp2-, and atp4- is a competitive inhibitor with respect to mg-atp2-. free mg2+ behaves as a mixed inhibitor on the kinetic with respect to the true enzyme substrate mg-atp2-, and eliminates the inhibition effect of this substrate. the kinetics with respect to mg-atp2- at non-inhibiting concentrations is not visibly affected by temperature of ph variation. the inhibiting effect of mg-atp2- is more m ...19852931236
ouabain-insensitive na+ stimulation of a microsomal mg2+ -atpase in gills of sea bass (dicentrarchus labrax l.).bass gill microsomal preparations contain a mg2+-dependent na+-stimulated atpase activity in the absence of k+, whose characteristics are compared with those of the (na+ + k+)-atpase of the same preparations. the activity at 30 degrees c is 11.3 mumol pi x mg-1 protein x hr-1 under optimal conditions (5 mm mgatp, 75 mm na+, 75 mm hepes, ph 6.0) and exhibits a lower ph optimum than the (na+ + k+)-atpase. the na+ stimulation of atpase is only 17% inhibited by 10-3m ouabain and completely abolished ...19852859946
effect of dietary n-6 and n-3 fatty acids on brain fatty acid composition in sea bass (dicentrarchus labrax l.). 19854041264
an anti-fucose agglutinin in the ova of dicentrarchus labrax. 19854068933
plasma essential amino acids changes in sea-bass (dicentrarchus labrax) after feeding diets deficient and supplemented in l-methionine.a fishmeal-based reference diet, a soybean-yeast-based methionine (met)-deficient diet and two met-supplemented diets were fed to groups of yearling sea-bass, reared in sea-water at 21 +/- 1 degrees c. levels of most free essential amino acids (eaa) reached a maximum concentration in plasma between 4 and 8 hr after a single meal. plasma met level remained very low with the deficient diet, exhibiting by 4 hr a 10-fold reduction when compared to the reference diet, although met content was divided ...19852864207
presence of tonofilaments and thymic serum factor (fts) in thymic epithelial cells of a fresh water fish (carp: cyprinus carpio) and a sea water fish (bass: dicentrarchus labrax).using indirect immunofluorescence we demonstrated the presence of fts in two fishes; the size of epithelial cells of the carp is smaller than of the bass.19863798525
effect of diets containing different oils on brain fatty acid composition in sea bass (dicentrarchus labrax l.).four groups of adult sea bass were given diets containing about 8% of one of four different oils having a different fatty acid composition: linseed oil, grape-seed oil, containing high amounts of linolenic and linoleic acids respectively, hydrogenated coconut oil, mainly containing saturated fatty acids, and cod liver oil which was considered as reference. total lipid, phospholipid and polar lipid contents of the brain of the different groups of sea bass were unaffected. the fatty acid compositi ...19863956152
purification and properties of the enzyme 6-phosphogluconate dehydrogenase from dicentrarchus labrax l. liver.the enzyme 6-phosphogluconate dehydrogenase (6-phospho-d-gluconate: nadp+ oxidoreductase, decarboxylating ec 1.1.1.44) from bass liver has been purified to over 95% of homogeneity by gel filtration, affinity and ion exchange chromatographies. the apparent molecular weight was estimated by gel filtration chromatography to about 100,000. analysis of the enzyme on sodium dodecyl sulphate polyacrylamide gel electrophoresis showed to be a dimeric protein. the effect of ph and kinetic properties were ...19863943305
delayed gametogenesis and spawning of sea bass (dicentrarchus labrax l.) kept under different photoperiod and temperature regimes.the present work investigates the importance of day length and temperature in the control of reproduction of sea bass, as well as the effectiveness of lhrha and hcg in inducing spawning out of season in this species. a controlled regime was produced and seasonal cycles with high components of temperature and photoperiod were extended from the summer solstice for at least 6 months, followed by a short photoperiod regime for 3 months before a new increase in these components. natural spawning in t ...198624233167
immunocytochemical identification and localization of the different cell types in the pituitary of the seabass (dicentrarchus labrax).antisera raised against chum salmon prolactin (prl), trout growth hormone (gh), mammalian adrenocorticotropic hormone (acth), thyroid-stimulating hormone (tsh), luteinizing hormone (lh), and alpha-melanophore-stimulating hormone (alpha-msh) were used to localize prl, gh, acth, gonadotropic, tsh, and msh cells in the hypophysis of the teleost dicentrarchus labrax using the unlabeled peroxidase anti-peroxidase method. in the rostral pars distalis, acth cells stained very intensively with anti-acth ...19863007272
identification of hormone-producing cells of the endocrine pancreas of the sea bass, dicentrarchus labrax, by ultrastructural immunocytochemistry.the hormone-producing cells of the endocrine pancreas of the sea bass dicentrarchus labrax have been identified by ultrastructural immunocytochemistry. the glucagon cells have "clear" cytoplasm and contain characteristic electron-dense polygonal granules surrounded by a "halo" of electron-lucent material. the insulin cells have numerous, tightly packed, electron-dense granules that are almost twice as large as the peripherally located granules of the somatostatin cells. the pancreatic polypeptid ...19862870004
annual cycle of plasma insulin and glucose of sea bass.dicentrarchus labrax, l.annual plasma insulin and glucose cycles were studied indicentrarchus labrax maintained in either seawater (37.8‰) or brackish water (3.5‰). in both media, the highest insulin levels were found during the prespawning period (august-november) coincident to increases in weight and a decrease in plasma glucose. during spawning (december-april) and postspawning (may-july) periods, the decrease in insulin occurred at the same time as a reduction in growth and an increase of plasma glucose. temperatur ...198724226260
na+-like effect of monovalent cations in the stimulation of sea bass gill mg2+-dependent na+-stimulated atpase.the mg2+-dependent ouabain insensitive-atpase activity present in gill microsomal preparations from dicentrarchus labrax is stimulated not only by na+ but also by k=, nh4+ or li+. these cations at 50-100 mm concentrations are similarly efficient to na+ in stimulating the enzyme activity with similar km values. whatever cation stimulates the activity, the enzyme is poorly sensitive to ouabain and 100% inhibited by 1.5-2.5 mm ethacrynic acid. all activity vs cation concentration curves show a biph ...19872962815
polyamine distribution and activity of their biosynthetic enzymes in the european sea bass (dicentrarchus labrax l.) compared to the rat.1. in the liver, heart and brain of the european sea bass, putrescine concentrations are much higher than in the equivalent rat tissues; spermidine and spermine levels are smaller. 2. ornithine decarboxylase in the bass liver is more active, but less stable than that in the rat; stability is acquired upon partial purification. bass liver adenosylmethionine decarboxylase activity is less than that found in the rat. both are activated and stabilized by putrescine. 4. the activating effect of putre ...19873427897
determination of glucose turnover in sea bass dicentrarchus labrax. comparative aspects of glucose utilization.1. parameters of in vivo glucose utilization by sea bass (132 +/- 6 g, mean +/- sem) acclimated at 15 degrees c in sea-water were measured after single injection of labelled glucose. 2. glucose turnover rate (rg; mumol . min-1 . kg-1) was found to be 0.55-065 (2-3h glucose) and 0.34 +/- 0.42 (u14c glucose). 3. glucose transit time was 443-449 min, glucose mass 233-261 mumol . kg-1, and glucose recycling 37%. 4. oxygen consumption (mo2) amounted to 94 +/- 6.2 mumol . min-1 . kg-1. 5. the comparis ...19873665443
localization of growth hormone releasing factor-like immunoreactivity in the hypothalamo-hypophyseal system of the frog (rana temporaria) and the sea bass (dicentrarchus labrax).using two different antisera, one raised against total human pancreatic growth hormone releasing factor (hpgrf) coupled through a two-step glutaraldehyde method and the other one raised against rat hypothalamic growth hormone releasing factor 1-10 (rgrf1-10), grf-like immunoreactivity was localized in the hypothalamo-hypophyseal system of the frog (rana temporaria) and the sea bass (dicentrarchus labrax). in the frog immunoreactive neurons were found in the nucleus preopticus, pars magnocellular ...19883141244
developmental transitions of myosin isoforms and organisation of the lateral muscle in the teleost dicentrarchus labrax (l.).in dicentrarchus labrax (the sea bass) the differentiation of lateral muscle fibres occurs at different stages and in different ways in the superficial (red), intermediate (pink) and deep (white) regions of the myotome. at hatching the myotomes are composed of presumptive white and red fibres, the latter forming a superficial monolayer present only near the transverse septum. at this stage, differences between the fibre types are mainly ultrastructural. from their different reactions with isofor ...19882972229
(na+ + k+)- and na+-stimulated mg2+-dependent atpase activities in kidney of sea bass (dicentrarchus labrax l.).1. sea bass kidney microsomal preparations contain two mg2+ dependent atpase activities: the ouabain-sensitive (na+ + k+)-atpase and an ouabain-insensitive na+-atpase, requiring different assay conditions. the (na+ + k+)-atpase under the optimal conditions of ph 7.0, 100 mm na+, 25 mm k+, 10 mm mg2+, 5 mm atp exhibits an average specific activity (s.a.) of 59 mumol pi/mg protein per hr whereas the na+-atpase under the conditions of ph 6.0, 40 mm na+, 1.5 mm mgatp, 1 mm ouabain has a maximal s.a. ...19882840241
peptidergic innervation of the adrenocorticotropic hormone (acth)- and growth hormone (gh)-producing cells in the pars distalis of the sea bass (dicentrarchus labrax).due to its unique organization, the teleost pituitary is an ideal model in which to investigate the relationship of the nervous system with the pituitary endocrine cells. a light microscope immunocytochemical study of the sea bass pituitary revealed six different neuropeptides in nerve fibers which projected into the pituitary neurohypophysis and bordered the adenohypophysial cells. double staining showed separate nerve fibers immunoreactive for corticotropin-releasing factor (crf), vasotocin (v ...19882904390
effects of diet and feeding time on daily variations in plasma insulin, hepatic c-amp and other metabolites in a teleost fish,dicentrarchus labrax l.juvenile sea bass, 1.5 years old, of mixed sex, held on long photoperiods were fed early on the photoperiod and late on the photoperiod, using different diets. fish fed natural diets showed a daily rhythmicity of plasma insulin, liver c-amp, plasma glucose, liver glycogen and muscle glycogen content, however, fish fed a commercial diet did not show this daily rhythmicity except for plasma insulin levels. in addition, these fish had significantly lower levels of plasma insulin, liver c-amp and pl ...198824226780
nadp-dependent isocitrate dehydrogenase from bass (dicentrarchus labrax l.) liver.the isocitrate dehydrogenase from bass liver was purified to homogeneity by gel filtration, affinity and ion exchange chromatographies. the molecular weight was estimated by gel filtration chromatography to about 120,000. analysis of the enzyme on sodium dodecyl sulphate polyacrylamide gel electrophoresis showed it to be a dimeric protein. the enzyme showed maximum activity in the ph range between 7.0 and 8.0 while its maximum activity was at ph 7.5. dl-isocitrate and mn2+ stabilized the enzyme, ...19883202883
glucose-6-phosphate dehydrogenase from dicentrarchus labrax liver: kinetic mechanism and kinetics of nadph inhibition.the kinetic mechanism of the reaction catalyzed by glucose-6-phosphate dehydrogenase (ec 1.1.1.49) from dicentrarchus labrax liver was examined using initial velocity studies, nadph and glucosamine 6-phosphate inhibition and alternate coenzyme experiments. the results are consistent with a steady-state ordered sequential mechanism in which nadp+ binds first to the enzyme and nadph is released last. replots of nadph inhibition show an uncommon parabolic pattern for this enzyme that has not been p ...19883196755
purification of 6-phosphogluconolactonase from bass (dicentrarchus labrax l.)liver.the enzyme 6-phosphogluconolactonase (ec 3.1.1.31) is present at high levels in bass liver. the enzyme has been purified 1253-fold with an overall yield of 78% in a procedure involving dye-ligand and gel filtration chromatographies. the purified enzyme which is homogenous by all the usual criteria has a molecular weight of about 30,000. it exhibits a considerably high catalytic efficiency with kcat/km of 8.5 x 10(7) m-1.s-1 at 22 degrees c. its activity illustrates the importance of glucose oxid ...19883245836
regulation of the pentose phosphate cycle in bass (dicentrarchus labrax l.) liver.the influence in the activities of the glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase produced by the ratio changes nadph/nadp is studied. the intracellular ratios of 20 and 10 are enough to achieve total inhibition of these two enzymes, respectively. measurements of a number of metabolic intermediates show that the concentrations of krebs cycle compounds are higher than those of glycolytic pathway metabolites. from a consideration of these values, the regulation of the p ...19883244891
metabolic regulation of glycolysis in sea bass (dicentrarchus labrax l.) muscle. i. kinetic study and characteristic modulators of pyruvate kinase.white muscle pyruvate kinase from sea bass presents positive cooperativity with respect to pep substrate. the enzyme is regulated by f-1.6-p2 and l-phenylalanine. the activator effect of f-1.6-p2 in experiments carried out for the substrate pep with crude extract seems to indicate that the enzyme is activated in vivo by this compound. the enzyme was not inhibited by either alanine or atp but was inhibited by l-phenylalanine. therefore this enzyme presents kinetic and regulatory properties simila ...19883244885
regulation of glycolysis in sea bass liver: phosphofructokinase isozymes.sea bass (dicentrarchus labrax l.) liver phosphofructokinase (pfk) presents biphasic kinetics with respect to fructose-6-phosphate (f-6-p) in experiments carried out with crude extract. after the enzyme had been purified, two isozymes have been detected after chromatographic treatment. the two isozymes present different kinetic behaviour pfk-l1, the first eluted phosphofructokinase activity shows positive cooperativity with respect to fructose-6-phosphate and pfk-l2, the second activity fraction ...19892528197
autoradiographic localization of binding sites for vasotocin in the brain and pituitary of the sea bass (dicentrarchus labrax).specific binding sites for vasotocin (vt) were detected in brain and pituitary of a teleost fish, the sea bass, after in vitro incubation of tissue sections with [3h]arginine-vasopressin (avp) and light microscopic autoradiography. conditions for the binding assay were optimized and as a result the binding was saturable and specific. in the brain [3h]avp binding was found to occur in the pars lateralis and the pars ventralis of the ventral telencephalon, in the pars centralis of the dorsal telen ...19892761757
immunocytochemical demonstration of close relationships between neuropeptidergic nerve fibers and hormone-producing cell types in the adenohypophysis of the sea bass (dicentrarchus labrax).light microscopic double immunocytochemical stainings, performed on sea bass hypothalamo-hypophysial sections, revealed the projection of different neuropeptide-immunoreactive neurons innervating the hormone-producing cell populations in the pituitary gland. in the rostral pars distalis (pd) the acth cells were found in close proximity to fibers immunoreactive for somatostatin (srif), growth hormone-releasing hormone (grf), corticotropin-releasing hormone (crf), vasotocin (vt), isotocin (it), su ...19892468554
the effect of ms 222 an anaesthetic on the peroxide metabolism enzymes in erythrocytes of freshwater and marine fish species.1. the effect of 70 mg/l and 35 mg/l ms 222 an anaesthetic on the enzymes: superoxide dismutase (sod), catalase (c) and peroxidase (p) were estimated in erythrocytes of cyprinus carpo, a freshwater fish and dicentrarchus labrax, a marine fish. 2. the end of the summer, at 16 degrees c ms 222 in concentration 70 mg/l caused an enhancement of the sod and peroxidase activities and a decrease of the catalase activity. 3. in the autumn at 22 degrees c sod and peroxidase activities in erythrocytes of ...19892566443
erythropoiesis and thrombopoiesis in the head-kidney of the sea bass (dicentrarchus labrax l.): an ultrastructural study.the head-kidney of the sea bass is a source of erythropoietic and thrombopoietic cells. no significant lymphopoietic activity is found. erythropoiesis, thrombopoiesis and granulopoiesis are intermingled, which suggests that only one environmental "niche" exists to modulate the lineage development. no numerous proerythroblasts are present. erythropoiesis consists of a proerythroblast, basophilic erythroblast, polychromatophilic erythroblast, acidophilic erythroblast, young erythrocyte and old ery ...19892513852
the influence of polyunsaturated fatty acids on spermine inhibition of lipoperoxidation. studies on liposomes prepared with microsomal and mitochondrial phospholipids of sea bass (dicentrarchus labrax l.) and rat liver.1. composition of phospholipids extracted from different organelles of european sea bass liver was determined and compared with that of phospholipids extracted from the same organelles of rat liver. 2. spermine binding to the vesicles prepared from microsomal and mitochondrial phospholipids and their aggregation was studied: these parameters indicate that only the presence of acidic phospholipids and not their unsaturation was essential for polyamine action. 3. no correlation exists between poly ...19892758801
granulopoiesis in the head-kidney of the sea bass (dicentrarchus labrax l.): an ultrastructural study.the ultrastructure of granulopoiesis in the head-kidney of the sea bass (dicentrarchus labrax l.), an euryhaline seawater teleost, was studied. the heterophilic, acidophilic and basophilic series consisting of promyelocyte, myelocyte, metamyelocyte and mature granulocyte stages are described. the granulopoietic pattern was similar to those of higher vertebrates but dissimilar to those of some other fish, suggesting that the vertebrate granulopoietic scheme was probably conserved during the evolu ...19902390328
the uptake metabolism and biological half-life of benzo[a]pyrene in different tissues of sea bass, dicentrarchus labrax.the disposition of polycyclic aromatic hydrocarbons in aquatic organisms is of interest from the viewpoint of both animal and human health. the kinetics of uptake and metabolism of benzo[a]pyrene (bap) were studied in various tissues of the marine fish, sea bass, upon intraperitoneal injection of the compound. a decrease in radioactivity occurred in all tissues and the calculated half-lives were 12.4 days for fat, 6.5 for kidney, 5.1 for intestine, 4.8 for gallbladder, 4.5 for spleen, 2.9 for mu ...19902090438
hyperplastic and hypertrophic growth of lateral muscle in dicentrarchus labrax (l.). an ultrastructural and morphometric study.in this em study of lateral muscle in dicentrarchus labrax, we observed that during the larval period, growth of the presumptive red and white muscle layers occurs both by hypertrophy (as fibres already present at hatching complete their maturation) and by production of new fibres in germinal zones specific to the two muscle layers. in the first half of larval life the presumptive white muscle increases in thickness by the addition, superficially, of new fibres derived from a germinal zone of pr ...19902240590
chronological appearance of the different hypophysial hormones in the pituitary of sea bass larvae (dicentrarchus labrax) during their early development: an immunocytochemical demonstration.antisera raised against chum salmon prolactin (prl), rainbow trout growth hormone (gh), mammalian adrenocorticotropic hormone (acth), thyroid-stimulating hormone (tsh), and luteinizing hormone (lh) were used to study the chronological appearance of immunoreactivity for prl, gh, acth, tsh, lh, and melanocyte-stimulating hormone (msh) in the pituitary of sea bass larvae (dicentrarchus labrax) during the first 26 days after hatching. the anti-acth gives positive immunostaining in the acth cells as ...19902186961
thyrotropin-releasing hormone-immunoreactive system in the brain and pituitary gland of the sea bass (dicentrarchus labrax, teleostei).the immunohistochemical distribution of thyrotropin-releasing hormone-like immunoreactivity (trh-ir) in the brain and pituitary of the sea bass (dicentrarchus labrax) was examined on cryostat sections of tissues perfuse fixed in a formaldehyde-glutaraldehyde mixture. trh-ir fibres were found in many areas of the brain: dorsal and ventral telencephalon, preoptic and tuberal hypothalamus, thalamus, midbrain tegmentum, optic tectum, and medulla oblongata. in the hypothalamus the densest area of inn ...19902125566
seasonal changes in plasma levels of gonadal steroids of sea bass, dicentrarchus labrax l.levels of plasma testosterone (t) and 11-ketotestosterone (11-kt) in males and plasma 17 beta-estradiol (e2), 17 alpha-20 beta-dihydroxy-4-pregnen-3-one (17 alpha,20 beta-dioh-p), and t in females were assayed by radioimmunoassay at monthly intervals throughout the sexual cycle of sea bass (dicentrarchus labrax l.). 17 alpha,20 beta-dioh-p was maintained at low levels (below 1 ng/ml) throughout the year, even during the spawning period (january-march). a bimodal seasonal pattern of plasma testos ...19902347486
radioimmunoassay of ovarian steroids in plasmas of ovulating female sea bass (dicentrarchus labrax).radioimmunoassays of the free and conjugated fractions of plasmas from ovulating sea bass (dicentrarchus labrax) have revealed the presence of several unusual polar steroids. among them is 3 alpha,17 alpha,20 beta,21-tetrahydroxy-5 beta-pregnane.19902354769
maturation of the endocrine pancreas in the sea bass, dicentrarchus labrax l. (teleostei): an immunocytochemical and ultrastructural study. i. glucagon-producing cells.the structure of the endocrine pancreas in the sea bass (dicentrarchus labrax l.) was studied with special reference to glucagon-immunoreactive cells. as described in most of the teleosts, the sea bass was found to have a diffuse pancreas. in the adult, endocrine cells were clustered in a principal islet and numerous accessory islets where the glucagon a cells were localized peripherally. under electron microscopy, the a cells displayed a clear hyaloplasm with granules having typical spherical o ...19902185122
stromal cells, macrophages and lymphoid cells in the head-kidney of sea bass (dicentrarchus labrax l.). an ultrastructural study.the ultrastructure of the stromal cells, macrophages and lymphoid cells in the head-kidney of the sea bass (dicentrarchus labrax l.) was studied. like mammals, stroma cell types here include endothelial and adventitial cells comprising the sinusoidal wall, fibroblast-like reticular cells related to scarce reticular fibres, and macrophage-type reticulum cells, the last probably corresponding to the resident macrophage population of higher vertebrates. their possible role in the haemopoietic micro ...19911954042
changes in plasma glucagon and insulin associated with fasting in sea bass (dicentrarchus labrax).juvenile sea bass (dicentrarchus labrax) were fasted for 22 days and changes in plasma insulin, glucagon and glucose levels, as well as glycogen and protein content in liver and muscle were analyzed. glucagon increased initially on the 4th day of fasting. the glucagon/insulin ratio (g/i) increased from a value of 0.11±0.02 (24h of fasting) to 0.21±0.05 (4th day of fasting). thereafter, both glucagon and insulin levels decreased and remained at low concentrations until the 22nd day of fasting. pl ...199124214669
autoradiographic distribution of galanin binding sites in the brain and pituitary of the sea bass (dicentrarchus labrax).specific binding sites for galanin (gal) were detected in brain and pituitary of a marine teleost fish, the sea bass, after in vitro incubation of tissue sections with [125i]gal and light microscopic autoradiography. binding conditions were optimized and as a result the binding was saturable and specific. in the brain, [125i]gal binding was found to occur in all parts of the dorsal and ventral telencephalon, in the anterior, tuberal and posterior hypothalamus, in the thalamus and in the tectum o ...19911712091
pancreatic endocrine cells in sea bass (dicentrarchus labrax l.) i. immunocytochemical characterization of glucagon- and pp-related peptides.pp-, pyy-, and glucagon-immunoreactive cells were immunocytochemically identified in the pancreatic islets of dicentrarchus labrax (sea bass). pyy cells also reacted with anti-pp serum. the specificity control showed that preabsorption of pp antiserum by pyy peptide abolished the immunostaining, while the reaction did not change when the pyy antiserum was preabsorbed by pp. these results suggested the existence of a pp/pyy molecule in the sea bass islets. the islet distribution of pp/pyy-immunor ...19912019394
fish plasma lipoproteins--comparative observations in serranides and sparides.1. diet, time from last feeding, temperature, season and sexual stage are some of the factors influencing the lipoprotein pattern. 2. keeping these factors constant species-specific differences observed among lipoprotein patterns of sparus aurata, puntazzo puntazzo, diplodus sargus, diplodus vulgaris and dicentrarchus labrax are discussed. 3. feeding habits and therefore lipid absorption and the rate of lipoprotein maturation process are the factors determining the observed differences.19911764905
immunoaffinity purification and partial characterization of sea bass (dicentrarchus labrax) growth hormone.growth hormone (gh) was isolated from sea bass (dicentrarchus labrax) pituitary extract by a simple one-step procedure involving immunoaffinity chromatography. a monoclonal antibody raised against chicken gh and found to immunostain very specifically the gh cells in the pituitary of the sea bass was coupled to cnbr-activated sepharose 4b. sea bass pituitary extracts were run on the affinity column, and the eluted material was analyzed on reversed-phase hplc and found to consist of one single pea ...19911916214
pancreatic endocrine cells in sea bass (dicentrarchus labrax l.) ii. immunocytochemical study of insulin and somatostatin peptides.insulin (ins)- and somatostatin (sst)-immunoreactive cells were demonstrated by light immunocytochemistry in the endocrine pancreas of sea bass (dicentrarchus labrax). ins-immunoreactive cells were identified using bovine/porcine, bonito, and salmon (s) ins antisera; the immunostaining was abolished when each antiserum was preabsorbed with its respective peptide but not with unrelated peptides. these cells also reacted with mammal (m) sst-28 (4-14) antiserum. the immunoreaction did not change wh ...19911673443
diplectanidae (monogenea) infestations of sea bass, dicentrarchus labrax (l.), from the spanish mediterranean area. histopathology and population dynamics under culture conditions.in the present study, diplectanum laubieri was redescribed from material obtained from wild and cultured fish. the population dynamics of d. aequans and d. laubieri under culture conditions was studied. the prevalence and mean intensity (average number of worms per parasitized fish) were 80.64% and 112 for d. aequans and 67.74% and 59.61 for d. laubieri, respectively. both diplectanidae exhibited seasonal variations, with maximal infection levels occurring in winter, suggesting continuous parasi ...19911866420
viral erythrocytic infection in sea bass: virus purification and confirmative diagnosis.the viral erythrocytic infection (vei) of sea bass (dicentrarchus labrax) is evidenced by the presence of inclusion bodies in the erythrocytes and erythroblasts. virus-like particles (veiv) about 135-150 nm in diameter were observed in erythroblasts of affected fish. no culturable virus could be recovered from the organs and blood of vei-affected fish, after inoculation of different fish cell lines. histochemical staining revealed the presence of rna but not of dna in the inclusion bodies. speci ...19911929880
the comparison of the effects of heavy metal ions on the antioxidant enzyme activities in human and fish dicentrarchus labrax erythrocytes.1. the effect of the increasing concentrations of cuso4 and hgcl2 (0.01-0.3 mmol/l) on erythrocyte haemolysis and the activities of peroxide metabolism enzymes: superoxide dismutase, catalase, peroxidase and glutathione peroxidase was investigated in human erythrocytes and the nucleated red blood cells of marine fish (dicentrarchus labrax). 2. the results show that both heavy metal ions had only little effect on haemolysis and antioxidant enzyme activities in human erythrocytes; in contrast the ...19921358529
cloning and sequencing of european sea bass (dicentrarchus labrax l.) growth hormone cdna using polymerase chain reaction and degenerate oligonucleotides.to clone and sequence the cdna of the growth hormone of european sea bass (dicentrarchus labrax l.) (sbgh), total pituitary rna was reverse transcribed and amplified using polymerase chain reaction (pcr). degenerate oligonucleotides, designed by comparing available gh cdna sequences from related teleost species, were used as primers to amplify the 5' end and the core region of sbgh cdna, while the 3' end was amplified according to the rapid amplification of cdna ends (race) method. sbgh cdna con ...19921472711
influence of blood sample collection on the haematocrit value of two teleosts: rainbow trout (oncorhynchus mykiss) and european sea bass (dicentrarchus labrax l.).1. the effects of the volume of blood extracted, number of extractions, and weight upon the haematocrit value of a freshwater teleost (oncorhynchus mykiss) and a marine one (dicentrarchus labrax) have been studied. 2. for trout with the same weight, the increase in the volume of blood extracted results in a significant increase in the haematocrit value. 3. for the same volume of blood extracted--in trout of the same weight--the second extraction results in a significant increase in the haematocr ...19921351449
subterminal hydroxylation of lauric acid by microsomes from a marine fish.microsomes from the liver of sea bass (dicentrarchus labrax) were shown to hydroxylate lauric acid at subterminal positions. the cytochrome p-450 system converted lauric acid to several mono-hydroxylated metabolites including omega-1 hydroxylaurate, which was the major metabolite (44% of total products). in addition, omega-2, omega-3, omega-4 and a small amount (2.3%) of omega hydroxylaurates were found. reaction products were identified using thin-layer chromatography (tlc) and gas chromatograp ...19921522763
ultrastructural changes induced by benzo[a]pyrene in sea bass (dicentrarchus labrax) liver and intestine: importance of the intoxication route.the ultrastructural effects of benzo[a]pyrene (bap) on sea bass (dicentrarchus labrax) liver and intestine were studied after experimental intoxication by two different routes: intraperitoneal injection and force-feeding. in both hepatocytes and enterocytes, the main structural perturbations concerned a large development of both rough and smooth endoplasmic reticulum and a great increase in the number of vacuoles and lysosomes in bap-treated fish. after 17 days of contamination, some nuclear cha ...19921740096
effects of starvation on valine and alanine transport across the intestinal mucosal border in sea bass, dicentrarchus labrax.kinetics of intestinal transport of l-alanine and l-valine (substrates of the a-system and the l-system, respectively, in mammals) across the brush-border membrane in sea bass, dicentrarchus labrax, were studied on intact mucosa using a short-term uptake technique. when fish were starved for 4-8 weeks, total influx (mucosa-to-cell) of valine fell owing to disappearance or modification of the diffusion component. the maximum influx rate of saturable component increased but its affinity (reflected ...19921401335
unfolding and trypsin inactivation studies reveal a conformation drift of glucose-6-phosphate dehydrogenase upon binding of nadp.binding of nadp to glucose-6-phosphate dehydrogenase (g6pd) from dicentrarchus labrax liver has stabilized its native structure against thermal inactivation, guanidine hydrochloride unfolding and inactivation by tryptic digestion. the time-course of g6pd inactivation by guanidine hydrochloride in the presence of nadp has provided experimental evidence in favor of a conformational drift upon nadp binding to the bass enzyme. based on the inactivation patterns obtained when the enzyme was treated w ...19921633201
lipid composition and mitochondrial respiration in warm- and cold-adapted sea bass.the response to cold of liver and heart membrane lipid composition and mitochondrial respiration in reared sea bass (dicentrarchus labrax l.) was investigated. fish acclimation was followed during the natural seasonal cycle from august to march. the data on the fatty acid composition of liver and heart polar lipids and on total lipids of liver mitochondria and microsomes did not indicate any increase in unsaturation in response to cold. the enzyme complexes of the liver and heart mitochondrial r ...19921406066
the uptake, metabolism, and biological half-life of benzo[a]pyrene administered by force-feeding in sea bass (dicentrarchus labrax).the kinetics of uptake and metabolism of benzo[a]pyrene (bap) were studied in various tissues of a marine fish, the sea bass (dicentrarchus labrax), after intragastric administration of pellets containing a 14c-labeled compound. only 25% of injected radioactivity was detected and it was found only in intestine, gallbladder, liver, and kidney. the major part of radioactivity was found in gallbladder (85% of the whole body radioactivity). the calculated half-lives determined after the decrease in ...19921374330
pathologic effects of sphaerospora dicentrarchi sitjà-bobadilla and alvarez-pellitero, 1992 and s. testicularis sitjà-bobadilla and alvarez-pellitero, 1990 (myxosporea: bivalvulida) parasitic in the mediterranean sea bass dicentrarchus labrax l. (teleostei: serranidae) and the cell-mediated immune reaction: a light and electron microscopy study.in the present study, the pathogenic effects of sphaerospora dicentrarchi and s. testicularis, histozoic and coelozoic myxosporean parasites of the mediterranean sea bass dicentrarchus labrax l., respectively, are described. the infection caused by the latter, which usually invades the testes and neighboring tissues, is considered to represent parasitic castration. s. dicentrarchi seems to be harmless except in massive infections, which probably result in organic disfunctions. the cellular host ...19938475029
immunolocalization of catecholamine enzymes, serotonin, dopamine and l-dopa in the brain of dicentrarchus labrax (teleostei).antisera to serotonin (5-ht), dopamine, and l-dopa, and to the catecholamine synthesizing enzymes, tyrosine hydroxylase (th), dopamine beta-hydroxylase (dbh), and phenylethanolamine n-methyl transferase (pnmt), were used to localize monoamine containing neurones in the brain of dicentrarchus labrax (sea bass). in the brain stem, 5-ht-immunoreactive (ir) neurones were recognized in the ventrolateral medulla, vagal motor area, medullary, and mesencephalic raphe nuclei and in the dorsolateral isthm ...19938098256
effects of cu, zn and cr salts on antioxidant enzyme activities in vitro of red blood cells of a marine fish dicentrarchus labrax.effects of xenobiotics (potassium dichromate, copper sulphate and zinc chloride) in vitro on antioxidant enzyme activities and lipid peroxidation in sea bass erythrocytes were investigated. total cell haemolysis was observed after 24 hr of exposure to 2 mm dichromate at 20 degrees c, 0.1 mm cuso(4) and 1 mm zncl(2). 24 hr exposure to non-haemolytic concentrations of cuso(4) and zncl(2) led to a concentration-related decrease in glutathione peroxidase activity. with dichromate, this activity was ...199320732259
gaba concentrations in different cerebral areas of bass (dicentrarchus labrax).in these investigations gaba concentrations in different cerebral areas (cortex, diencephalon, optic lobes and mesencephalon) of bass (dicentrarchus labrax) were evaluated. according to the results obtained, the gaba, like other chemical mediators (noradrenaline, dopamine, serotonin), investigated in different animal species, shows a variable distribution in the cns of bass. the highest levels of gaba were observed in the cerebral cortex and the lowest ones in the mesencephalon. mean values were ...19938060601
lipid composition and microsomal atpase activities in gills and kidneys of warm- and cold-acclimated sea bass (dicentrarchus labrax l.).the response to cold of gill and kidney membrane lipid composition and microsomal (na(+)+k(+))-atpase, na(+)-atpase and mg(2+)-atpase activities in reared sea bass (dicentrarchus labrax l.) was investigated. fish acclimation was carried out according to the seasonal cycle from august to march. no cold-promoted increase in fatty acid unsaturation was shown in gill and kidney polar lipids and in total lipids of mitochondria and microsomes. in both tissues the (na(+)+k(+))-atpase exhibited positive ...199324202871
mitochondrial dna sequence variation in the european sea bass, dicentrarchus labrax l. (serranidae): evidence of differential haplotype distribution in natural and farmed populations.pcr and direct sequencing of 300 to 377-bp fragments of the cytochrome b mitochondrial gene were carried out in 40 specimens of european sea bass, dicentrarchus labrax l., collected at different sites in the mediterranean basin and representing wild and farmed populations. sequence analysis revealed 6 transitional changes, which generated 5 different haplotypes (a-e). only one mutation was nonsynonymous because it occurred in the first position of a codon leading to the replacement of valine by ...19938193667
augmentation of protein synthesis and degradation by poor dietary amino acid balance in european sea bass (dicentrarchus labrax).sea bass fry were fed a fixed ration of one of six isonitrogenous diets differing in essential amino acid balance or physical and chemical state of the protein source (hydrolysate vs. intact protein) to induce different growth rates. the reference diet was based on fish meal, whereas the other diets contained fish protein hydrolysate, greaves meal (i.e., defatted collagen meal) or hydrolyzed feather meal added at 30 or 50% of crude protein at the expense of fish meal protein. digestibility as we ...19938410368
ultrastructural and cytochemical observations on the sporogenesis of sphaerospora testicularis (protozoa: myxosporea) from mediterranean sea bass, dicentrarchus labrax (l.).the ultrastructure and cytochemical features of sphaerospora testicularis found in the testes of cultured sea bass (dicentrarchus labrax) are described. a hypothesis for the developmental cycle of this myxosporean in the lumen of seminiferous tubules is suggested. the initial stage, a primary cell (p), generates by endogenous division a secondary cell (s) which divides mitotically producing two s cells. the latter divide again by endogeny generating tertiary cells (t) within them. after mitotic ...199323195545
sequence of the mitochondrial trna(thr) and trna(pro) genes from european seabass, dicentrarchus labrax. 19937684836
differences in chromatin condensation during spermiogenesis in two species of fish with distinct protamines.the sperm cells of mullus surmuletus (family mullidae, order perciformes) and dicentrarchus labrax (family percichthyidae, order perciformes) belong respectively to "type i" and "type ii" spermiogenesis categorized by mattei ('70). the protein content in their sperm nuclei consists of two histone-like proteins (mullus surmuletus) and one typical protamine (d. labrax). in order to correlate the molecular characteristics of these proteins with their function, we have analyzed the molecules in deta ...19938423442
detection and identification of a pathogenic marine mycobacterium from the european seabass dicentrarchus labrax using polymerase chain reaction and direct sequencing of 16s rdna sequences.mycobacteriosis has become a major concern for the commercial mariculture of the european sea bass dicentrachus labrax in israel. the disease remains asymptomatic for a long time, is virtually impossible to eradicate with antibiotics, stunts the growth of the fish and renders the fish unmarketable. the pathogen was identified as mycobacterium marinum by direct sequencing and analysis of approximately 600 bp of the pathogen ribosomal encoding dna (rdna). the polymerase chain reaction technique wa ...19938293073
population dynamics of sphaerospora dicentrarchi sitja-bobadilla et alvarez-pellitero, 1992 and s. testicularis sitja-bobadilla et alvarez-pellitero, 1990 (myxosporea: bivalvulida) infections in wild and cultured mediterranean sea bass (dicentrarchus labrax l.).the population dynamics of sphaerospora dicentrarchi and s. testicularis, myxosporean parasites of sea bass (dicentrarchus labrax), was studied in different groups of cultured and wild fish. s. dicentrarchi prevalence was higher for wild fish (100%) than for cultured ones (70.5%). infection levels increased with host age and there were no significant sex differences in cultured fish. among parasitized organs, the gall bladder and intestine registered the highest infection levels in wild and cult ...19938479799
primary culture of gill epithelial cells from the sea bass dicentrarchus labrax.we have developed the first explant technique that allows the in vitro study of gill physiology and biochemistry in marine species. gill fragments were cultured at 17 degrees c, in atmospheric pco2, with nutrient medium (leibovitz l15), ph 7.8, supplemented with 10% fetal bovine serum and adjusted to the osmolarity of fish plasma (350 mosm/liter). coating plates with collagen, gelatin, or polylysin did not improve our results. decrease in osmotic pressure, removal of bovine serum, or its replace ...19948193773
ovarian melanotropic peptides and adaptation in two teleostean species: sparus aurata l. and dicentrarchus labrax l.the ovarian tissue of dicentrarchus labrax and sparus aurata displays two immunoreactive peaks that correspond to the elution time of human des-acetyl alpha-msh [acth(1-13)-amide] and human alpha-msh. in view of the close identity between the primary structure of fish and human alpha-msh, these data demonstrate that two msh-related peptides are present both in sea bream and sea bass ovary. alpha-msh-like immunoreactivity was found within both granulosa and thecal layers of mature follicles, as w ...19947984515
non-specific cytotoxic response against tumor target cells mediated by leucocytes from seawater teleosts, sparus aurata and dicentrarchus labrax: an ultrastructural study.the in vitro cytotoxic reaction of leucocytes from the seawater teleosts gilthead seabream (sparus aurata) and sea bass (dicentrarchus labrax) against tumor target cells was studied by transmission and scanning electron microscopy. head-kidney, blood or peritoneal exudate leucocytes were incubated with hela or b16 melanoma cells. after incubation, conjugates of leucocytes (effectors) and tumor cells (targets) were observed. both the effector-target cell binding and target cell lysis steps of the ...19947880589
phagocytic defence mechanism in sea bass (dicentrarchus labrax l.): an ultrastructural study.the ultrastructure of the phagocytic process in fish has not been established in spite of the significant morphofunctional differences detected in the fish immune system with respect to the basic immunological pattern in vertebrates. we report the ultrastructure of the bacterial phagocytic defence mechanism in sea bass (dicentrarchus labrax l.).19947879910
the prolactin of european sea bass (dicentrarchus labrax l.): cloning of cdna and efficient expression in escherichia coli.the cdna encoding sea bass (dicentrarchus labrax) prolactin (sbprl) was obtained by reverse transcription-polymerase chain reaction (rt/pcr) from pituitary rna with degenerate primers designed on the basis of the cdnas of the two prls (tprl188 and tprl177) from the tilapia, oreochromis niloticus. the sbprl cdna encodes a preprotein of 212 amino acids composed of a putative signal peptide of 24 residues and a mature protein of 188 amino acids that is the homologue of tiprl188. the cdna coding for ...19947804137
cloning and characterization of the european seabass, dicentrarchus labrax, mitochondrial genome.mitochondrial dna (mtdna) from the european seabass, dicentrarchus labrax, has been cloned and characterized. its gene organization was deduced by a comparison of the sequenced termini of different subclones obtained from european seabass mtdna to the completely-sequenced mtdnas from carp and freshwater loach. the difference in genome size between the european seabass mtdna (approximately 18 kb) and most of the other characterized fish mtdnas (approximately 16.5 kb) is accounted for by the displ ...19948001168
ontogeny of the endocrine cells of the intestine and rectum of sea bass (dicentrarchus labrax l.): an ultrastructural study.several endocrine cell types were ultrastructurally characterized during the differentiation of the intestine and rectum of sea bass (dicentrarchus labrax l.) larvae. only one cell type (type i) was found in the posterior region of the undifferentiated gut of 5-day-old larvae (phase i). types v and vi were found in both the intestine and rectum, types ii, iii and iv in the intestine, and types vii and viii in the rectum of 9- and 12-day-old larvae (phase ii), the rectum alone showing signs of fu ...19947893007
ontogeny of the endocrine cells of the stomach of sea bass (dicentrarchus labrax l.): an ultrastructural study.the endocrine cells present in the developing stomach of sea bass larvae have been characterized ultrastructurally. only one endocrine cell type (type i) was found in the presumptive stomach of 9- and 12-day-old larvae, one (type ii) and five (types iii, iv, v, vi and vii) in the aglandular stomach of 32-, and of 39- to 46-day-old larvae, respectively, and five (types iii, viii, ix, x and xi) in the differentiated stomach of 55- and 60-day-old larvae. a maturation process was established for som ...19947887502
design and performance of an accurate demand feeder for the study of feeding behaviour in sea bass, dicentrarchus labrax l.a new demand feeder was designed for the automatic and accurate feeding of fish. the feeding device is microcomputer controlled and permits the continuous recording of feeding behaviour. the electromechanical feeder consists of a sliding door powered by a solenoid which provides only one weighed pellet when activated by the fish. some preliminary results on feeding behaviour in sea bass are presented to test the efficiency of the feeder.19947800750
an enzyme immunoassay for salmon gonadotropin-releasing hormone and its application to the study of the effects of diet on brain and pituitary gnrh in the sea bass, dicentrarchus labrax.the effects of two different diets [diet 1 (d1), high protein-low carbohydrate; diet 2 (d2), low protein-high carbohydrate] on brain and pituitary gonadotropin-releasing hormone (gnrh) contents, as well as circulating steroids and vitellogenin, were studied over the reproductive period of the sea bass. salmon gnrh was measured using a newly developed competitive enzyme immunoassay with an enzymatic tracer made of sgnrh covalently coupled to acetylcholinesterase from the electric organ of the eel ...19947821783
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