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differential actions of a mammalian gonadotropin-releasing hormone antagonist on gonadotropin-ii and growth hormone release in goldfish, carassius auratus.in goldfish the two native forms of gonadotropin-releasing hormone (gnrh), salmon gnrh (sgnrh) and chicken gnrh-ii (cgnrh-ii), stimulate both gonadotropin-ii (gth-ii) and growth hormone (gh) release. modifications of gnrh structure at positions 1, 2, 3, and 6 often result in an antagonist in goldfish, an observation well documented in mammalian studies. in a preliminary study in goldfish, a mammalian gnrh antagonist, [ac-d(2)nal1, 4cl-d-phe2, d(3)-pal3,6, arg5, d-ala10]-mgnrh (analog l) weakly s ...19948084380
organization of inner ear endorgan projections in the goldfish, carassius auratus.cytoarchitectural analysis of the octavolateralis area of the goldfish, carassius auratus, reveals that as in other teleosts, five first-order octaval nuclei are present: the anterior octaval, magnocellular, descending, tangential, and posterior octaval nuclei. the descending nucleus appears to be anatomically specialized relative to that of the halecomorph amia calva and many teleosts in that a large dorsomedial subpopulation of the nucleus lies medial to nucleus medialis, a first-order lateral ...19948038983
sperm morphology and distribution of intramembranous particles in the sperm heads of selected freshwater teleosts.the morphology of spermatozoa and the distribution of intramembranous particles (imps) in sperm-head membranes in teleostean fish were examined ultrastructurally to clarify the presence of characteristic arrays (parallelogram or hexagon in packing) of imps. the following four species of fish were used: goldfish (carassius auratus), loach (misgurnus anguillicaudatus), flat bitterling (acheilognatus rhombeus), sweetfish (plecoglossus altivelis). it was demonstrated that spermatozoa of all these fi ...199318621254
characterization of d1 receptors mediating dopamine-stimulated growth hormone release from pituitary cells of the goldfish, carassius auratus.previously, we demonstrated that dopamine (da) stimulates gh release from the pituitary of goldfish, and this action is mediated by d1-like receptors. in the current study, we have provided evidence for the presence of d1-specific binding sites in the pituitary cells of goldfish. these d1-binding sites were found to be saturable, stereospecific, and selective for d1 ligands. the rank order of binding affinity of these d1-binding sites is (+)sch23390 > skf83566 > (-)sch23390 > domperidone > ly171 ...19938102094
in vitro synthesis of 20α-reduced and of 11- and 21-oxygenated steroids and their sulfates by testes of the goldfish (carassius auratus): testicular synthesis of corticosteroids.testes from spermiating goldfish were incubated with [(3)h]17-hydroxyprogesterone. the major products in the unconjugated fraction were identified as androstenedione, androstenetrione, 11-β-hydroxyandrostenedione, 11-ketotestosterone, 17,20α-dihydroxy-4-pregnen-3-one (17,20αp) and 11-deoxycortisol. testosterone was present predominantly in the glucuronide fraction, but yields were low (1-3%). the major components of the sulfate fraction were 17,20αp and 11-deoxycortisol. the identification of co ...199324202487
dopamine functions as a growth hormone-releasing factor in the goldfish, carassius auratus.in vivo and in vitro approaches have been used to examine the role of dopamine (da) as a growth hormone (gh)-releasing factor in the goldfish. da stimulated gh release from perifused pituitary fragments of goldfish in a dose-dependent manner. the gh-releasing effect of da was seasonal, being the highest in sexually regressed fish, intermediate in recrudescent fish, and the lowest in sexually mature (prespawning) fish. the gh response to da was blocked by the d1 antagonist (+)sch23390, confirming ...199324202463
intracellular mechanisms mediating gonadotropin and growth hormone release in the goldfish, carassius auratus.evidence for the involvement of ca(2+), protein kinase c, camp, and arachidonic acid metabolism in mediating gonadotropin (gth) and growth hormone (gh) release in the goldfish is reviewed. models for the signal transduction pathways mediating gth-releasing hormone (gnrh) and dopamine actions on gth and gh secretion are postulated. a novel hypothesis that two gnrhs which bind to the same receptor type activate different transduction cascade in two different cell types (gth vs. gh) as well as with ...199324202457
acoustic response properties of single units in the torus semicircularis of the goldfish, carassius auratus.single units of the goldfish torus semicircularis (ts) were recorded in response to pure tones. response areas (ra) were obtained by recording the number of spikes evoked by tones in a range of frequencies and levels within the units' dynamic range. ras gave estimates of best sensitivity (bs), characteristic frequency (cf), most excitatory frequency at each level (bf), and q10db. peri-stimulus-time histograms (psth), interspike interval histograms (isih), and period histograms were obtained at v ...19938366473
electrically fused-egg induction and its development in the goldfish, carassius auratus.in this study, we report the induction of cell fusion between two fertilized eggs and viable chimeric fish from the fused egg in goldfish. chemical fusion by polyethylene glycol between denuded fertilized egg induced egg adhesion but rarely egg fusion. this treatment seemed not suitable for egg fusion, because of tight adhesion between vitelline membrane and surrounding matrix. electrically fertilized egg fusion was successfully induced at the rate of almost 100% under conditions of 400v/cm, 1 m ...19938398675
involvement of protein kinase c in agonist-stimulated goldfish ovulation.the effects of two protein kinase c (pkc) inhibitors, calphostin c and staurosporine, on the in vitro ovulation of goldfish (carassius auratus) oocytes were investigated. ovulation was stimulated by prostaglandin (pg) f2 alpha (pgf2 alpha, 2.0 micrograms/ml), by sodium orthovanadate (0.1 mm), by a combination of the phorbol ester phorbol 12-myristate-13-acetate (pma, 0.1 micrograms/ml) and calcium ionophore a23187 (0.05 micrograms/ml), by thapsigargin (0.2 micrograms/ml), and by elevated ph (8.1 ...19937683501
the depth profile of electrically induced tectal sustained potential shift responses in the goldfish (carassius auratus).tectal sustained potential shifts (spss) were recorded in response to electrical stimulation of the tectal surface in immobilized goldfish using saline-filled glass microelectrodes. the peak amplitudes of surface recorded sps responses were negative, this negativity declining with increasing tectal depth, reversing in polarity at a depth of ca. 350 microns and subsequently increasing in positivity. these opposing sps polarities are attributed to field potentials generated by the source and sink ...19938476383
prostaglandin-induced female spawning behavior in goldfish (carassius auratus) appears independent of ovarian influence.this study was conducted to determine whether prostaglandin f2 alpha (pgf)-induced spawning behavior in female goldfish (carassius auratus) is influenced by sex steroids or by the stage of ovarian development (assessed by gonadosomatic index (gsi), ovary weight expressed as a percentage of body weight). in two groups of intact females with gsi values ranging from 0.2 to 16.6% (experiment 1) and 0.6 to 12.7% (experiment 5), respectively, there was a significant positive correlation between pgf-in ...19938440516
1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (mptp), and gamma-vinyl-gamma-aminobutyric acid (gamma-vinyl gaba) alter neurotransmitter concentrations in the nervous tissue of the goldfish (carassius auratus) but not the cockroach (periplaneta americana).1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (mptp), 1-methyl-4-phenylpyridinium iodide (mpp+) and gamma-vinyl-gamma-aminobutyric acid (gamma-vinyl gaba) are drugs demonstrated to alter catecholamine or gamma-aminobutyric acid (gaba) concentrations in vertebrate nervous tissue. mptp and mpp+, which are potent and selective vertebrate neurotoxins, are effective in depleting noradrenaline and dopamine concentrations in goldfish. however, only mpp+ depletes dopamine in the central nervous tissues o ...19938094992
inhibition of adenylate cyclase activity in the goldfish melanophore is mediated by α₂-adrenoceptors and a pertussis toxin-sensitive gtp-binding protein.the signal-transduction system that mediates the melanosome-aggregating response in melanophores of the black-moor goldfish, carassius auratus, was investigated by examining the inhibition of adenylate cyclase activity mediated by α-adrenoceptors in cultured cells. when the melanophores were incubated with 1 mmol·1⁻¹ 3-isobutyl-1-methylxanthine for 5 min, the intracellular level of cyclic adenosine-3',5'-monophosphate increased two- to three-fold. norepinephrine at 100 nmol· 1⁻¹ and naphazoline ...199318816892
effects of experimentally induced hyperammonemia on glial fibrillary acidic protein (gfap) in the rhombencephalon of goldfish (carassius auratus l.).this experimental study was made to know the effect of hyperammonemia on glial fibrillary acidic protein (gfap) in the glial cells of posterior rhombencephalon in the goldfish (carassius auratus l.). hyperammonemia was induced by elevating the ammonia concentration in the tank water to 0.88 mm with ammonium chloride; the ammonia level in the control tank water was < 0.1 mm. the gfap levels were measured at 8, 16, 30, 60, 90 and 120 days. gfap was quantified with a digital analysis system and a t ...19938387165
a coccidian (apicomplexa: eimeriidae) with extracytoplasmally located stages in the kidney tubules of golden carp (carassius auratus gibelio l.) (cyprinidae).numerous coccidian stages were found in the kidney tubules of the golden carp (carassius auratus gibelio). the merogonial and gamogonial stages were localized extracytoplasmally in the microvillous region of the epithelial cells. the host-parasite interface consisted of i) a large area where the parasite was separated from the host cytoplasm by the parasitophorous vacuole membrane only, and ii) a zone of multiple fusions of the host cell membrane investing the parasite to the neighbouring microv ...19938325562
hormonal influences on in vitro [(35)s]-sulfate uptake by gill arches from the goldfish (carassius auratus l.).a bioassay for insulin-like growth factor (igf), based on the in vitro incorporation of [(35)s]-sulfate into gill arch tissue was used to study the hormonal regulation of proteoglycan synthesis in the goldfish (carassius auratus). [(35)s]-sulfate incorporation into gill arch tissue was found to be time-dependent with maximal uptake occurring by 48h, suggesting that proteoglycan synthesis in this tissue was maintained for at least 48h in vitro. the addition of human recombinant igf-i (igf-i) to t ...199324202499
homeobox genes are expressed in the retina and brain of adult goldfish.the goldfish (carassius auratus) visual pathway displays continuous growth and plasticity throughout life. since homeobox genes are important transcriptional regulators in development, we searched for homeobox genes in the adult goldfish retina and brain. using the pcr, we discovered a repertoire of homeobox sequences expressed in these tissues. in addition to isolating homeodomain sequences found in the vertebrate hox gene clusters, a sequence identical to the chicken chox7 homeodomain was char ...19938096640
spread of the bacterial fish pathogen aeromonas salmonicida after importation of infected goldfish, carassius auratus, into australia. 19938117214
multiple loci for synapse protein snap-25 in the tetraploid goldfish.the common goldfish carassius auratus is tetraploid and has 100 chromosomes. we describe here goldfish cdna clones for snap-25, a 200-amino-acid synaptosome-associated protein that has remained highly conserved during evolution. snap-25 occurs as a single-copy gene in mouse, chicken, and drosophila melanogaster. sequences of six distinct goldfish cdna clones and southern hybridizations show that the goldfish has three, or possibly four, snap-25 loci rather than two as expected. a gene duplicatio ...19938248151
cloning and characterization of a truncated dopamine d1 receptor from goldfish retina: stimulation of cyclic amp production and calcium mobilization.receptors for dopamine are present on horizontal cells of fish retina that are linked to the activation of adenylate cyclase. in the present study, the goldfish (carassius auratus) gene that encodes these receptors, referred to as gfd1, was isolated and analyzed. a single open reading frame within the gfd1 gene encodes a protein of 363 amino acids that is highly homologous with dopamine d1 receptors from rats and humans. interestingly, the carboxyl terminus of gfd1 lacks 80 amino acids that are ...19938264547
expansion of genes that encode mhc class i molecules in cyprinid fishes.we have analyzed the genomic genes and the mrna that encode mhc class i molecules in cyprinid fishes, namely, the ginbuna crucian carp (carassius auratus langsdorfii) and the carp (cyprinus carpio). the presence of several distinct class i genes was revealed in the genome of cyprinid fishes, and distinct class i genes that are expressed in carp cells were identified. the sequences of the alpha 3 domain of these class i genes are relatively well conserved, whereas the sequences of the respective ...19938326125
in vitro characterization of gonadotropin-releasing hormone antagonists in goldfish, carassius auratus.the two native forms of gnrh, salmon gnrh and chicken gnrh-ii, in the brain and pituitary of goldfish are both active in stimulating gonadotropin-ii (gth-ii) and gh release. the objective of the present study was to characterize gnrh antagonists for their ability to inhibit sgnrh- and cgnrh-ii-induced gth-ii and gh release in goldfish using a pituitary fragments perifusion system. contrary to expectations, putative gnrh antagonists with d-arg6 stimulated gth-ii and gh release in nearly all cases ...19938404604
goldfish calcitonin: purification, characterization, and hypocalcemic potency.a novel teleost calcitonin was isolated from the goldfish, carassius auratus, and its amino acid sequence was determined to be h-cys-ser-ser-leu-ser-thr-cys-val-leu-gly- lys-leu-ser-gln-glu-leu-his-lys-leu-gln-thr-tyr-pro-arg-thr-asn-val-gly- ala-gly-thr-pro-nh2. the structure of goldfish calcitonin (gct) was similar to that of salmon calcitonin (sct) but differed from the latter at positions 3, 27, and 29. the hypocalcemic activity of gct was estimated to be 3,470 iu/mg by the standardized rat ...19938454163
molecular and cellular physiology of aromatase in the brain and retina.due to exceptionally high brain aromatase activity, teleost fish are advantageous for studying neural aromatase regulation, localization, and physiology. to determine the molecular mechanism of enhanced expression, we have isolated, cloned and sequenced a 3 kb full-length aromatase cdna from a goldfish (carassius auratus) brain library using a human placental aromatase cdna as probe. the deduced sequence of goldfish aromatase is 510 amino acids (predicted mw, 58 kda) with 69% overall sequence si ...19938476767
immunocytochemical and biochemical evidence for aromatase in neurons of the retina, optic tectum and retinotectal pathways in goldfish.using an animal model in which neural aromatase is apparently overexpressed (the goldfish, carassius auratus) and an anti-human placental antibody which specifically crossreacts with goldfish brain aromatase, aromatase-immunoreactive neuronal cell bodies and fibers have been localized within the retina. these include a subset of horizontal cells, bipolar cells, and amacrine cells of the inner nuclear layer, some fibers of the outer and inner synaptic layers and certain cells of the ganglion cell ...19938680435
characterization of basic proteins from goldfish myelin.myelin basic protein (mbp) from common goldfish (carassius auratus) myelin was extracted with dilute mineral acid. immunological cross-reactivity of the goldfish mbp, with polyclonal antisera raised against bovine mbp, suggested that the goldfish protein has epitopes for these antibodies. it also reacted with a monoclonal antibody specific for a seven amino acid epitope (130-137) conserved in the mbp of most mammalian species. to characterize the charge heterogeneity of this protein, we iodinate ...19937678038
topographic organization of descending projection neurons to the spinal cord of the goldfish, carassius auratus.several neurons from different nuclei give rise to descending spinal tracts and project to various levels in the spinal cord of goldfish, carassius auratus. these were visualized by retrograde transport of horseradish peroxidase (hrp) administered to the bilaterally transected spinal cord at 6 levels, corresponding to 1st, 5th, 10th, 15th, 20th and 25th segments of the vertebral column. as many as 16 brain nuclei or neuronal aggregations and the mauthner cells project posteriorly up to the 20th ...19937690299
segmental arrangement of reticulospinal neurons in the goldfish hindbrain.the hindbrain is evolutionarily conserved among diverse vertebrate phyla. in vertebrate embryos, the hindbrain is segmentally organized as a series of overt swellings known as rhombomeres. in the larval zebrafish brachydanio rerio, conspicuous and identifiable reticulospinal neurons are positioned in the center of rhombomeres. segmentally homologous reticulospinal neurons that share a range of morphological, developmental, and biochemical features occupy adjacent rhombomeres. we have recently sh ...19938454739
neuroanatomical substrate for the dorsal light response. i. differential afferent connections of the lateral lobe of the valvula cerebelli in goldfish (carassius auratus).the afferent connections of the lateral lobe of the valvula cerebelli in goldfish were investigated by retrograde labeling with horseradish peroxidase (hrp). retrogradely labeled neurons were observed ipsilaterally in the lateral nucleus of the valvula and contralaterally in the inferior olivary nucleus after hrp injection into all parts of the lateral valvula. the valvulopetal projections from these nuclei were topographically arranged. after hrp injection confined to the rostral half of the la ...19938387162
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
neurotensin, substance p, gastrin/cholecystokinin, and bombesin in the intestine of the tilapia (oreochromis mossambicus) and the goldfish (carassius auratus): immunochemical detection and effects on electrophysiological characteristics.the distribution of neurotensin-, substance p-, gastrin/cholecystokinin/carerulein- and bombesin-like immunoreactivities has been studied in the gut of the tilapia (oreochromis mossambicus) and the goldfish (carassius auratus) using immunohistochemistry and radioimmunoassay; the electrophysiological effects of these peptides on the intestinal epithelium were also examined with the ussing-type chamber technique. neurotensin- and gastrin/cholecystokinin/caerulein-like immunoreactivities were prese ...19921283377
role of intracellular calcium in renal proximal tubule cell volume regulation.osmoregulatory ca2+ signaling in hypotonic solutions was studied with videometric techniques in 158 proximal renal tubules isolated from the teleost carassius auratus. absence of extracellular ca2+, hypoxia (23 mmhg), or nacn (3 mm) did not alter regulatory volume decreases (rvd). nevertheless, decrements of intracellular ca2+ via the a23187 ionophore or after intracellular ca2+ chelation with indo-1/am (5 microm) inhibited rvd. in tubules depleted of ca2+, rvd could only be fully elicited when ...19921332517
oxoanions stimulate in vitro ovulation and signal transduction pathways in goldfish (carassius auratus) follicles.the present study investigated the effects of a number of oxoanion compounds on in vitro ovulation of goldfish follicles and ovarian second messenger activities. significant levels of ovulation were induced by 0.1 mm sodium chromate, 0.1 mm sodium metavanadate, 10 mm sodium molybdate, 0.1 mm sodium orthovanadate, 5 mm sodium selenate, 0.5 mm sodium tungstate, and 0.1 mm vanadyl sulfate. at levels that significantly stimulated ovulation, metavanadate, molybdate, orthovanadate, tungstate, and vana ...19921332498
biotransformation of the flame retardant mc-984 by goldfish, carassius auratus. 19921421851
ependymins from the cerebrospinal fluid of salmonid fish: gene structure and molecular characterization.so far, ependymins (epds) have been sequenced only from cypriniform fish, and in the past all attempts have failed to characterize, on a molecular level, homologous epd proteins in higher vertebrates. therefore, rainbow trout (oncorhynchus mykiss) epds, which represent the predominant proteins of the cerebrospinal fluid, have been n-terminally sequenced and the encoding cdna subsequently cloned using the polymerase chain reaction. surprisingly, only 40-42% of the amino acids are identical with t ...19921511892
a parkinsonian syndrome induced in the goldfish by the neurotoxin mptp.parkinson's disease has been modeled in humans, lower primates, and to a lesser extent in some other vertebrates by administration of the potent neurotoxin mptp (1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine). the mptp model has thus drawn considerable attention as a system to search for anti-parkinson's disease drugs, although the cost and scarcity of primates has limited extensive applications. we now report that a parkinsonian syndrome can be elicited in the common goldfish (carassius auratus) ...19921521741
fmrfamide-like immunoreactivity in the brain and pituitary of the goldfish, carassius auratus.the distribution of fmrfamide-like immunoreactivity was determined in the brain and the pituitary of the goldfish, carassius auratus. immunoreactive perikarya were observed in the olfactory nerve, nucleus entopeduncularis, nucleus anterioris periventricularis, nucleus posterioris periventricularis, lateral part of the nucleus lateralis tuberis pars posterioris, midbrain tegmentum, and medulla oblongata. immunoreactive fibers were widely distributed in the brain, in particular in the ventral tele ...19921354419
evoked responses from an in vitro slice preparation of a primary gustatory nucleus: the vagal lobe of goldfish.the vagal lobe of goldfish (carassius auratus) is a laminated structure in which primary gustatory afferents terminate in a stereotypical pattern. because the afferent fibers enter and distribute within the lobe in the transverse plane, the structure appeared suitable for in vitro slice electrophysiology. slices were cut on a vibratome at 400-800 microns thickness and placed in a fresh water teleost ringer's solution. following a recovery period, clear population responses were recorded followin ...19921504805
maturation of the goldfish (carassius auratus) erythrocyte.1. cohorts of [3h]thymidine-labelled erythrocytes were examined over a 42-day period in goldfish (carassius auratus l.) recovering from phenylhydrazine hcl-induced anemia under normoxic conditions at 20 +/- 1 degree c and maintained with minimal disturbance on a high nutritional plane. 2. as judged by changes in primary and derived hematological variables, maturation required 16-20 days. 3. similar estimates were obtained using cytomorphic variables obtained by image analysing methods. 4. these ...19921351805
effects of lesions of the optic nerve, optic tectum and nervus terminalis on rod precursor proliferation in the goldfish retina.teleost retinas grow throughout life by proliferation of neuroblasts at the retinal margin and dedicated rod precursors in the outer nuclear layer. mechanisms regulating this proliferation are largely unknown. previous investigators observed that rod precursor replication, as detected by incorporation of radioactive thymidine into cells of the outer nuclear layer, is enhanced after optic nerve crush. we attempted to determine whether this was due to severing of the retinopetal (nervus terminalis ...19921515918
reversed-phase ion-paired hplc of purine nucleotides from skeletal muscle, heart and brain of the goldfish, carassius auratus l.--ii. influence of environmental anoxia on metabolite levels.1. the type and the amounts of some (di)nucleotides in white skeletal muscle, heart and brain of anoxic goldfish were established with a reversed-phase ion-paired hplc method. 2. significant changes in the levels of these metabolites, as compared to controls, were observed. the most consistent change is the increase of imp and of imp-load (imp/atp + adp + amp) in the three tissues during anoxia. 3. adenylate energy charges are maintained at a high level in the anoxic white muscle and the anoxic ...19921611875
reversed-phase ion-paired hplc of purine nucleotides from skeletal muscle, heart and brain of the goldfish, carassius auratus l.--i. development of the analytical method.1. a reversed-phase ion-paired liquid chromatographic (hplc) method was developed to measure amp, adp, atp, imp, nad+ and nadp+ levels in white muscle, heart and brain of anoxic goldfish. 2. mobile phase parameters of the hplc method (concentrations of buffer, organic modifier and counter-ion, and ph) were varied to establish the optimal conditions for separation of the compounds of interest. 3. the analytical method was evaluated by calculating some relevant chromatographic parameters (reproduc ...19921611874
n-methyl-d-aspartate receptor antagonist mk-801 impairs learning but not memory fixation or expression of classical fear conditioning in goldfish (carassius auratus).the amnestic effects of the noncompetitive antagonist mk-801 on visually mediated, classic fear conditioning in goldfish (carassius auratus) was examined in 5 experiments. mk-801 was administered 30 min before the training session on day 1 to look for anterograde amnestic effects, immediately after training to look for retrograde amnestic effects, and before the training or test session, or both, to look for state-dependence effects. the results showed that mk-801 produced anterograde amnesia at ...19921534239
hyperammonemia induces transient gfap immunoreactivity changes in goldfish spinal cord (carassius auratus l.).in this study we have demonstrated that high ammonia concentration in tank water induces changes in the glial fibrillary acidic protein (gfap) of ependymal cells and radial astrocytes in the goldfish spinal cord. hyperammonemia was induced by elevating the ammonia concentration in the tank water to 0.88 mm using ammonium chloride; ammonia in control water was less than 0.1 mm. immunohistochemical methods were used for gfap and vimentin, and levels were measured at 4, 8, 16, 30, 60, 90 and 120 da ...19921319021
sustained potential shift responses and their relationship to the ecg response during arousal in the goldfish (carassius auratus).1. goldfish, when presented with a 10 sec light-on stimulus against a background of 2 hr of sensory restriction, exhibited sustained potential shift (sps) activity, of differing polarity, at each of four surface recording sites, on the medulla, cerebellum, optic tectum and telencephalon. 2. principle components analysis (pca) indicated that sps responses from each region comprised superimposed early and late waveforms. at the cerebellar, tectal and telencephalic surfaces, neuronal activity appea ...19921348678
dopamine stimulates growth hormone release from the pituitary of goldfish, carassius auratus, through the dopamine d1 receptors.previously, we have demonstrated that ip injection of apomorphine, a nonselective dopamine (da) agonist, increases serum gh levels in the goldfish, suggesting a possible role of da in gh regulation. in the present study, the effects of da on gh release in the goldfish were further characterized using an in vitro perifusion system for pituitary fragments. da increased gh release in a dose-dependent manner with an ed50 of 0.26 +/- 0.06 microm. skf38393, a da d1 agonist, mimicked the gh-releasing e ...19921347006
the effects of temperature change and transient hypoxia on auditory nerve fiber response in the goldfish (carassius auratus).temperature change and hypoxia produce consistent, reversible effects on the response of single auditory nerve fibers in the goldfish. cooling and hypoxia produce reductions of a cell's spontaneous activity, sensitivity, most excitatory or best frequency (bf) at a given signal level, and overall responsiveness to acoustic stimulation. warming above ambient temperatures increases a cell's spontaneous activity, sensitivity, bf, and responsiveness. adaptation, or the tendency for responsiveness to ...19921348502
effects of temperature on the in vivo and in vitro multiplication of trypanosoma danilewskyi laveran et mesnil.temperature directly affected the in vivo and in vitro multiplication of trypanosoma danilewskyi laveran et mesnil. the parasitemia in experimentally infected goldfish (carassius auratus l.) increased rapidly at 20 degrees c and reached its peak in 3 to 5 weeks post-infection. the multiplication was slower at 10 degrees c. the parasitemia declined after the peak at 20 degrees c. lowering of temperature of the infected goldfish from 20 degrees c to 10 degrees c slowed multiplication of the parasi ...19921644346
partial glycinergic denervation induces transient changes in the distribution of a glycine receptor-associated protein in a central neuron.the effect of partial glycinergic denervation on the cellular distribution of the 93 kda peripheral polypeptide associated with the glycine receptor was studied at the level of the teleost mauthner cell, an identified neuron of the goldfish brain (carassius auratus). previous studies using monoclonal antibodies raised against purified glycine receptors and immunoperoxidase staining have shown that these proteins are localized in clusters on the entire surface of this neuron. specifically, the 93 ...19921309572
effective loci and roles of acetylcholine in temperature regulation of goldfish.microinjections of acetylcholine (ach) and carbachol were made into discrete forebrain loci in goldfish (carassius auratus) to evaluate the importance of cholinergic mechanisms for behavioral thermoregulation. injections of 5, 10, 25, and 50 micrograms ach into the far anterior nucleus preopticus periventricularis (npp) (r. peter and v. gill. j. comp. neurol. 159: 69-102, 1975) and immediately adjacent ventral telencephalon led to consistent dose-dependent decrease in selected temperature. no ef ...19921415647
afferents to the oculomotor nucleus in the goldfish (carassius auratus) as revealed by retrograde labeling with horseradish peroxidase.the goal of this work was to compare the distribution and morphology of neurons projecting to the oculomotor nucleus in goldfish with those previously described in other vertebrate groups. afferent neurons were revealed by retrograde labeling with horseradish peroxidase. the tracer was electrophoretically injected into the oculomotor nucleus. the location of the injection site was determined by the antidromic field potential elicited in the oculomotor nucleus by electrical stimulation of the ocu ...19921401270
ascending general visceral pathways within the brainstems of two teleost fishes: ictalurus punctatus and carassius auratus.the primary general visceral nucleus in goldfish (carassius auratus) and catfish (ictalurus punctatus) is located at the ventroposterior boundary of the vagal gustatory lobe and receives coelomic visceral, but not gustatory inputs. the neuronal tracer horseradish peroxidase (hrp) was employed to visualize sources of input to and ascending projections from the primary general visceral nucleus in these species. in addition, immunocytochemical techniques were utilized to define the cytological divi ...19921629401
functional organization of vagal reflex systems in the brain stem of the goldfish, carassius auratus.the coordination of secretory and motor responses to food within the alimentary canal requires well organized brain stem reflex systems. in the goldfish, carassius auratus, three vagal reflex systems control three phases of ingestion and digestion. the orobranchial system sorts food from substrate, the pharyngeal chewing organ prepares items deemed to be food for digestion and absorption, and the abdominal system regulates the digestion of food. each system is represented in the central nervous ...19921619041
a morphological study of abducens nucleus motoneurons and internuclear neurons in the goldfish (carassius auratus).the location and distribution of abducens (abd) nucleus motoneurons (mn) and internuclear neurons (int) were determined in the goldfish (carassius auratus) by means of horseradish peroxidase and fluorochrome retrograde labeling. abd mn were labeled following tracer injection into the ipsilateral lateral rectus muscle. these mn were arranged in two ventrolateral clusters along the rostro-caudal axis of the posterior brainstem. both groups of neurons showed a similar number of cells, and their axo ...19921540841
visible light-inducible photolyase gene from the goldfish carassius auratus.by introducing and expressing a cdna library constructed from mrna of the cultured goldfish carassius auratus cells in escherichia coli, a gene encoding photolyase of the vertebrate was isolated, the first example from metazoa. the amino acid sequence deduced from the nucleotide sequence differs significantly from those of microorganisms. five out of 6 tryptophan residues strictly conserved in photolyases from microorganisms and thought to play important roles in dna and chromophore binding of t ...19921339447
psychometric functions for level discrimination and the effects of signal duration in the goldfish (carassius auratus): psychophysics and neurophysiology.classical conditioning of respiration was used to obtain psychometric functions for pulsed tone level discrimination in the goldfish (carassius auratus). conditioned respiratory suppression is a graded response that has some properties of a confidence rating measure. these properties were used to obtain receiver operating characteristics (roc) and psychometric functions using a blocked method of constant stimuli. empirical rocs and neurometric functions were also obtained for single auditory-ner ...19921512323
the laboratory maintenance of sanguinicola inermis plehn, 1905 (digenea: sanguinicolidae).methodology is described for the laboratory maintenance of the life-cycle of sanguinicola inermis, using common carp (cyprinus carpio) as the definitive host and lymnaea peregra as the intermediate host. lymnaea auricularia was also infected but is not considered to be a suitable laboratory host. tench (tinca tinca) were susceptible to infection at high cercarial doses but subsequent infection rates were low. goldfish (carassius auratus) and lymnaea stagnalis were refractory to laboratory infect ...19921614729
neurotransmitter release from hair cells and its blockade by glutamate-receptor antagonists.to assess the mechanism by which glutamate-receptor antagonists block afferent discharge at the hair cell synapse, we examined the effects of these and other agents on sound-evoked excitatory post-synaptic potentials (epsps) and on spontaneous miniature post-synaptic potentials (mepsps) in auditory-nerve fibers of the goldfish (carassius auratus) saccule. a quantal analysis of synaptic transmission under conditions in which the probability of transmitter release was reduced by cobalt, an agent t ...19911676396
distribution of central melatonin binding sites in the goldfish (carassius auratus).in fish, as well as in birds and mammals, the pineal hormone melatonin acts as a neuroendocrine transducer of photoperiod and as such has a profound influence over the timing of seasonal behavior, especially reproduction. with the aim of better understanding how melatonin may exert its influence in the fish, we have studied the distribution and characteristics of the melatonin binding sites in the brain and pituitary of the goldfish (carassius auratus) using the ligand [2-(125)i]iodomelatonin an ...199119912786
the use of fluorescent microspheres in the study of piscine macrophage aggregate kinetics.the kinetics of piscine liver, spleen, and kidney macrophage aggregate formation was studied in carassius auratus using the sequential interperitoneal injection of fluorescent green and yellow microspheres. this study indicates that 1. macrophages migrating to or forming new aggregates move randomly throughout the aggregate mass and do not simply increase aggregate size by a laminating process (layer upon layer), 2. macrophages apparently form new aggregates and migrate to existing aggregates si ...19912060686
a monoclonal antibody raised against the mauthner cell also recognizes some reticular neurons.a monoclonal antibody was raised against dissected mauthner cells of goldfish, carassius auratus. the immunoglobulin (mab 222c2) recognized in this neuron a determinant that was localized on the soma of the mauthner cell in front of the axon hillock and on the dorsomedial portion of the initial third of its ventral dendrite. when observed with electron microscopy, the staining was associated with polyribosomes and with the reticulum, close to the golgi cisternae. the antibody also labelled other ...19912057063
structural characterization of the melano-macrophage centres (mmc) of goldfish carassius auratus.in the present work we have studied the organization of melano-macrophage centres (mmcs) in the peripheral lymphoid organs, including spleen, pro- and mesonephros, of the goldfish, carassius auratus, in an attempt to clarify their cellular composition, origins and functional relationships. histological analysis demonstrated a similar organization in the three organs on the basis of closely packed phagocytic cells containing abundant pigment. the mmcs of carassius auratus are found throughout the ...19911954065
retinal regeneration in teleost fish.the neural retina in teleost fish can regenerate after surgical or neurotoxic destruction. whereas in amphibians the retina regenerates by transdifferentiation of pigmented retinal epithelial cells, in goldfish (carassius auratus) the source of regenerated retinal cells is a population of scattered proliferating cells located in the outer nuclear layer within the differentiated retina. these proliferating cells are modified neuroepithelial cells termed 'rod precursors' because in the intact reti ...19911752162
accumulation of tri-n-butyltin chloride and triphenyltin chloride by oral and via gill intake of goldfish (carassius auratus).1. the bioconcentration factors (bcf) of both chemicals via gill intake of goldfish reached plateaux after 21 days of exposure. the average bcf values of bu3sncl and ph3sncl (n = 2) were 1976 and 1384, respectively, after 21-28 days of exposure. 2. the bcf values by oral intake of goldfish reached plateaux after 28 days for bu3sncl but did not for ph3sncl. the bcf values of bu3sncl and ph3sncl were 0.04 and 0.10, respectively, after 35 days. 3. the order of the bcf values via gill intake was rev ...19911675973
use of confocal microscope for the cellular analysis of the glycine synaptic receptor.the presence of glycine receptors was examined with a monoclonal antibody and indirect immunofluorescence on reticular neurons of the goldfish (carassius auratus) brainstem. images of thin (0.6 microns) optical sections were recorded from 80 microns thick specimen with a confocal microscope thus obviating the need for mechanical slicing. due to the reduced out-of-focus noise, high resolution was obtained. lookthrough projections were computer generated. compared with classical methods involving ...19911653340
synergistic induction of ovulation and prostaglandin synthesis in goldfish (carassius auratus) follicles by sodium orthovanadate and hydrogen peroxide.the effects of hydrogen peroxide (h2o2) and sodium orthovanadate (na3vo4) on ovulation and prostaglandin (pg) production were investigated in goldfish (carassius auratus) follicles. h2o2, at levels that did not stimulate ovulation, significantly increased the ability of na3vo4 to induce ovulation. the enhancing effect of h2o2 on na3vo4-induced (10 microm) ovulation was observed over a wide range of concentrations (0.3-19.2 ppm) but was maximal at 1.2-4.8 ppm. the h2o2 effect on ovulation diminis ...19911805995
masking and suppression in auditory nerve fibers of the goldfish, carassius auratus.the responses of single fibers of the auditory nerve of the goldfish (carassius auratus) were recorded in response to two tones of different duration (20 ms 'signals' and 200 ms 'maskers') presented simultaneously or non-simultaneously. a single tone may produce excitation, adaptation, and suppression in auditory nerve fibers. for fibers with characteristic frequencies (cf) in the 200 to 400 hz range, frequencies well above cf tend to produce suppression. if the net response to the masker tone i ...19911757285
influences of norepinephrine, and adrenergic agonists and antagonists on gonadotropin secretion from dispersed pituitary cells of goldfish, carassius auratus.static incubations of dispersed goldfish pituitary cells with 1-100 nm norepinephrine (ne) stimulated gonadotropin (gth) release. additions of the alpha-agonist phenylephrine, and the alpha 1-agonist 6-fluoronorepinephrine, but not the alpha 2-agonist clonidine, nor the beta-agonist isoproterenol, also enhanced gth secretion. the gth responses to 1 nm ne was significantly inhibited by coincubations with 1 microm of the alpha-antagonist phentolamine, the alpha 1-antagonists prazosine and benoxath ...19911682833
circadian rhythms of melatonin secretion from superfused goldfish (carassius auratus) pineal glands in vitro.a flow-through, whole-organ culture (superfusion) system was developed, and goldfish pineal glands were maintained at 25 degrees under light-dark (ld) 12:12 cycles, reversed ld 12:12 cycles, continuous dark (dd), or continuous light (ll) conditions for 48 hr. under ld 12:12 and reversed ld 12:12 cycles, superfused pineal glands showed a rhythmic melatonin secretion: scotophase was associated with high titers and photophase with low titers. the melatonin secretion rhythms persisted for two cycles ...19911879667
erythrocyte fractionation by velocity sedimentation and discontinuous density gradient centrifugation.investigation of development, maturation and senescence in fish red blood cells depends on effective separation methods. preliminary to initiation of studies of this type the erythrocytes of goldfish,carassius auratus, and rainbow trout,oncorhynchus mykiss, were fractionated by velocity sedimentation at unit gravity or discontinuous percoll density gradient centrifugation in an attempt to separate and characterize enriched populations of juvenile and mature cells. cytomorphological variables wer ...199124213719
incorporation of yolk fatty acids into body lipids of goldfish (carassius auratus l.) larvae raised at two different temperatures.in five separate experiments, eggs from a single female goldfish were fertilized at 20°c. they were incubated at 22°c for 6 hours, after which some of the eggs were transferred to 13°c. when a defined post-hatch developmental stage was reached, lipid extracts were prepared from larvae, both with yolk sacs intact and after removal of the yolk sac by dissection. other larvae were sampled at yolk exhaustion. gas chromatographic analysis of fatty acid profiles revealed that larvae incorporated 16:0, ...199124213711
compartmentalization of prostaglandin synthesis within the fish ovary.numerous studies have shown that the follicle walls surrounding mature vertebrate oocytes are capable of producing primary prostaglandins. however, very few studies have looked at the prostaglandin synthetic potential of other ovarian tissue components. in brook trout (salvelinus fontinalis) and goldfish (carassius auratus), mature follicle walls can produce prostaglandins e and f (pge and pgf, respectively); however, it is apparent that several other tissues within the fish ovary also produce s ...19912035698
dl-2-amino-4-phosphonobutyric acid does not eliminate "on" responses in the visual system of goldfish.dl-2-amino-4-phosphonobutyric acid (apb) suppresses activity in retinal on pathways. it is generally assumed that loss of the on pathway would result in loss of on responses in the visual system. we tested this assumption by recording activity from the optic nerves of intact goldfish (carassius auratus) before and after intraocular injection of apb. whole-nerve responses to increments and decrements of light were compared to electroretinogram responses and to tectal evoked potentials. apb severe ...19912023929
organization and development of horizontal cells in the goldfish retina, i: the use of monoclonal antibody at101.we have produced and characterized a monoclonal antibody, at101, which selectively labels both viable and formaldehyde-fixed horizontal cell axon terminals, but not their somas or axons, of the goldfish (carassius auratus) retina. the antigen recognized by at101 appears to be a cell surface glycoprotein with a molecular weight of about 35,000 daltons, and is present exclusively or predominantly in nervous tissues of all vertebrate species examined. we have used at101 as a probe to analyze immuno ...19912059569
trypanosoma danilewskyi in carassius auratus: the nature of protective immunity in recovered goldfish.trypanosoma danilewskyi is pathogenic to goldfish, carassius auratus; the number that survived an infection was related to the size of inoculum, i.e., the mortality was low when the inoculum was small. most fish that had prior exposure(s) to the parasite survived subsequent homologous challenge(s) and were protected for at least 89 days. the immunity was nonsterile as low numbers of parasites were detected in the blood of some recovered fish. intraperitoneal injection of corticosteroid in recove ...19912010858
effects of serotonin on gonadotropin and growth hormone release from in vitro perifused goldfish pituitary fragments.the effects of serotonin (5-ht) on gonadotropin and growth hormone release from perifused goldfish (carassius auratus, l.) pituitary glands were studied. serotonin, at micromolar concentrations, caused a dose-related release of gonadotropin and an inhibition of growth hormone release in pituitaries from goldfish at different sexual stages. at lower concentrations 5-ht continued to inhibit growth hormone release, but had no effects on gonadotropin release. the stimulatory effects of 5-ht on gonad ...19911874380
immunohistochemical localization of glycine receptors and a linked polypeptide in the goldfish brain.three monoclonal antibodies were used to examine with immunocytochemistry the distribution of the glycine receptors and the related 93kd polypeptide in the adult goldfish brain (carassius auratus). one immunoglobulin recognizes the 48kd strychnine-binding subunit of the receptor and the two others bind to the peripheral 93kd polypeptide which is coupled to the receptor molecules. immunofluorescent spots were visualised with all three antibodies on the somatic and dendritic membrane of the cells. ...19911653341
glial fibrillary acidic protein in the fish optic nerve.the intermediate filament glial fibrillary acidic protein (gfap) is the predominant cytoskeletal protein of mature glial cells in the mammalian nervous system. the nervous systems of lower vertebrates, such as fish, have been examined for the presence of gfap and several investigators have shown that goldfish (carassius auratus) brain contains gfap-positive astrocytes. the same studies have demonstrated that, in contrast to the brain, the optic nerve of goldfish did not show any gfap immunoreact ...19911718861
enhancement of repair of uv-irradiated plasmids in cultured fish cells by fluorescent light preillumination and growth arrest.the uv-irradiated plasmid pbscatsv, which could express chloramphenicol acetyltransferase (cat) in the presence of sv40 early promoter, was transfected into rbcf-1 cells derived from the goldfish (carassius auratus). the cells were incubated in the dark for 24 h and then the cat activity was measured. cat expression relative to non-irradiated control was calculated. the cat expression of the exponentially growing cells transfected with uv-irradiated plasmid was enhanced by fluorescent light (fl) ...19911719399
melatonin deacetylation: retinal vertebrate class distribution and xenopus laevis tissue distribution.deacetylation is a rapid clearance mechanism for ocular melatonin. we have studied the distribution of retinal melatonin deacetylase activity among vertebrate classes. exogenous radiolabeled melatonin is metabolized by ocular tissue prepared from the amphibian xenopus laevis, the reptile anolis carolinensis, the teleost fish carassius auratus, and the bird gallus domesticus. in contrast, we were unable to detect ocular melatonin breakdown in rat or pig. in each species exhibiting ocular melatoni ...19911782560
goussia carpelli (apicomplexa, eimeriorina) from cyprinid fish: field observations and infection experiments.intestinal tissue samples of 9 cyprinid and gobiid fish species from several hatcheries and ponds in south bohemia were found to harbour goussia carpelli-like coccidian oocysts. furthermore, laboratory transmission of goussia carpelli, obtained from common carp, was attempted to 9 cyprinid fish species, both laboratory reared and obtained from pond environments. infection experiments, carried out by fecal contamination (direct transmission) and by using tubificid oligochaetes as paratenic hosts ...19911928799
lack of involvement of arachidonic acid metabolism in chicken gonadotropin-releasing hormone ii (cgnrh-ii) stimulation of gonadotropin secretion in dispersed pituitary cells of goldfish, carassius auratus. identification of a major difference in salmon gnrh and chicken gnrh-ii mechanisms of action.gonadotropin (gth) release in static incubations of dispersed goldfish pituitary cells was stimulated by chicken gth-releasing hormone ii (cgnrh-ii), salmon (s)gnrh, phospholipase a2, phospholipase c, phospholipase d, and arachidonic acid (aa). coincubations with nordihydroguaiaretic acid (ndga), 5,8,11,14-eicosatetraenoic acid, and indomethacin did not alter the gth responses to cgnrh-ii. in contrast, ndga reduced sgnrh-stimulated gth release. incubation with ca(2+)-deficient medium abolished t ...19911936548
synchronous neurite branchings in single goldfish retinal ganglion cells.we have examined the time course of branch formation in neurites of retinal ganglion cells isolated from adult goldfish (carassius auratus). these neurites elongate at approximately 13 microns/h, and usually branch by bifurcation of growth cones at their tips. the times elapsed between branchings in different neurites of single cells can be described by a poisson distribution with a mean interval of approximately 2 h. as predicted by this distribution, a relatively large number of branchings occ ...19912069904
the development of a noncompetitive enzyme-linked immunosorbent assay for oncorhynchid growth hormone using monoclonal antibodies.the development of a sensitive and specific two-site, or sandwich, noncompetitive enzyme-linked immunosorbent assay (elisa) for oncorhynchid growth hormone (gh) using monoclonal antibodies (mcas) is reported. the mcas were generated by the fusion of myeloma cells with spleen cells from mice that had been immunized with chum salmon (oncorhynchus keta) recombinant gh. the mcas specifically recognized the gh-secreting acidophils in the proximal pars distalis of immature male rainbow trout (oncorhyn ...19911879674
habituation in goldfish (carassius auratus) is impaired by increased interstimulus interval, interval variability, and telencephalic ablation.goldfish (carassius auratus) were fitted with electrodes and buccal catheters for monitoring electrocardiograms and ventilations, respectively. a 2-s "light-on" stimulus was repeatedly presented to groups of fish at fixed interstimulus intervals (isis) of 1 or 2 min or at variable isis with a mean duration of 1 or 2 min. normal fish, fish with telencephalic ablation, and fish with sham operations were compared for responsiveness and habituation to repeatedly presented stimuli. the longer the isi ...19902285485
photoaffinity labeling of pituitary gonadotropin-releasing hormone receptors in goldfish (carassius auratus).receptors for gnrh were labeled by use of an iodinated (125i) photoreactive gnrh derivative [d-lys6-azidobenzoyl]-gnrh. this derivative was found to bind to two classes of gnrh binding sites: high-affinity/low-capacity sites and low-affinity/high-capacity sites. the binding affinity of [d-lys6-azidobenzoyl]-gnrh was found to be greater than that of d-lys6-gnrh, but lower than a superactive fish gnrh agonist [d-arg6, trp7, leu8, pro9-net]-gnrh (sgnrh-a). analysis of the photoaffinity-labeled gold ...19901963320
gill sphaerosporosis in goldfish (carassius auratus).infections caused by a sphaerospora sp. resembling s. chinensis are reported for the first time in goldfish (carassius auratus) from north america. the myxosporean was found in the respiratory epithelium of the gill of pond-reared fish. spores from stained tissue sections were spherical with an equal mean length and width of 6.3 microns. spore valves were thickened at the suture which lies in a plane perpendicular to two prominent pyriform polar capsules. the polar capsules were 4.0 x 2.8 micron ...19902250337
suppression and excitation in auditory nerve fibers of the goldfish, carassius auratus.the suppression of background spike activity in the absence of deliberate acoustic stimulation occurs in fibers of the goldfish saccular nerve tuned in the region of 250 hz. suppression is most robust in the frequency range between 450 and 1050 hz, the range of cf for the mid- and high-frequency saccular fibers. suppression of background activity tends to occur following the suppressor tone offset ('off-suppression'), even though the spike response during the suppressor is below the background r ...19902249963
orthovanadate and fluoroaluminate stimulate inositol phosphate production and in vitro ovulation in goldfish (carassius auratus) follicles.both sodium orthovanadate and fluoroaluminate were found to stimulate in vitro ovulation in intact goldfish follicles, suggesting the involvement of g-proteins in ovulation. although orthovanadate was able to stimulate camp production, it probably stimulates ovulation by some other mechanism since camp blocks ovulation in this species. these agents also stimulated the accumulation of labeled inositol phosphate in follicle walls. the time course of inositol phosphate production showed a slightly ...19902165827
thermal acclimation and muscle contractile properties in cyprinid fish.after several weeks of cold acclimation, the swimming performance of some fish is increased at low temperatures and decreased at high temperatures. the temperature compensation of locomotory activity involves changes in central patterns of muscle fiber recruitment and in the properties of the peripheral nervous system and muscle tissues. in some freshwater fish belonging to the family cyprinidae, including the goldfish (carassius auratus), the common carp (cyprinus carpio), and the roach (rutilu ...19902143635
developmental incompatibility between cell nucleus and cytoplasm as revealed by nuclear transplantation experiments in teleost of different families and orders.teleosts from different families and orders were used as materials for nuclear transplantation experiments. (1) the nuclei of goldfish (carassius auratus, family cyprinidae, order cypriniformes) were transplanted into the enucleated egg cytoplasm of loach (paramisgurnus dabryanus, family cobitidae, order cypriniformes) and vice-versa. (2) the nuclei of tilapia (oreochromis nilotica, order perciformes) were transplanted into the enucleated egg cytoplasm of goldfish (carassius auratus, order cypri ...19902386727
possible role of basolateral cell membrane in proximal renal tubule osmoregulation.the cellular response to hypotonic stimulation was studied with videometric methods in 266 proximal renal tubules dissected from carassius auratus (goldfish). in hypotonic solutions (low nacl), cells underwent rapid swelling followed by gradual shrinking toward isotonic volume (volume-regulatory decrease phase, vrd). hypothermia (8 degrees c), increased extracellular potassium (15, 25, and 40 mm), quinine (0.1 mm), barium (0.5 mm), 4,4'-diisothio-cyanostilbene-2,2'-disulfonic acid (dids; 0.02 mm ...19902331023
[regional specificity within plasma membrane and nuclear membrane of goldfish sperm].combined sem and tem technique including thin sectioning, freeze-fracture and etching as well as cytochemical staining have been used for ultrastructural study on goldfish (carassius auratus) sperm. it has been shown that primitive sperm plasma membrane and nuclear membrane are differentiated with regional specificity. the results from this study can be summarized as follows: 1. intercalated protein particles are highly organized in the plasma membrane in the certain region of the head to form c ...19902382525
differential distribution of serotoninergic inputs on the goldfish mauthner cell.the morphology and distribution of the serotoninergic (5-ht) input to the mauthner cell (m cell) of a teleost, carassius auratus, were analyzed at the light microscopic level. immunohistochemical methods revealed that 1) most fibers innervating the m cell originate from the ventral and lateroventral regions of the rhombencephalon; 2) two groups of fibers contribute to this innervation, thick ones (type i, 0.4-0.7 microns in diameter) with terminal endings and thin ones (type ii, less than 0.2 mi ...19902319013
use of a pituitary cell dispersion method and primary culture system for the studies of gonadotropin-releasing hormone action in the goldfish, carassius auratus. i. initial morphological, static, and cell column perifusion studies.two cell dispersion methods for excised goldfish pituitary glands were tested, and a cultured dispersed cell system based on trypsin enzymatic tissue digestion was developed and characterized. controlled trypsin/dnase treatment of goldfish pituitary gland yielded dispersed cells of high viability (trypsin blue exclusion test) that responded to gonadotropin (gth)-releasing hormone (gnrh) challenges with gth secretion in a time- and dose-dependent manner following overnight culture. electron micro ...19902407601
seasonal changes in serum gonadotropin, testosterone, 11-ketotestosterone, and estradiol-17 beta levels and their relation to tumor burden in gonadal tumor-bearing carp x goldfish hybrids in the great lakes.the hybrids of carp (cyprinus carpio) and goldfish (carassius auratus) collected from the lower great lakes between 1978 and 1981 exhibited a high frequency of gonadal neoplasms and apparent sterility, conditions which were rare in the parental species. a pronounced hyperplasia of gonadotropic cells in hybrids resulted in the accumulation of large stores of biologically active gonadotropin (gth) in the pituitary gland. serum gth levels were generally higher in hybrids than in carp collected from ...19902307342
use of a pituitary cell dispersion method and primary culture system for the studies of gonadotropin-releasing hormone action in the goldfish, carassius auratus. ii. extracellular calcium dependence and dopaminergic inhibition of gonadotropin responses.primary static cultures of dispersed goldfish pituitary cells obtained by controlled trypsinization released gonadotropin (gth) in response to 2-hr stimulations of 0.1 nm to 1 microm [trp7,leu8]-gonadotropin-releasing hormone (sgnrh), [d-arg6,pro9-n-ethylamide]-sgnrh (sgnrha), and [his5,trp7,tyr8]-gnrh (cgnrh-ii) in a dose-dependent manner. coincubation with 10 to 1000 nm of a dopamine agonist, apomorphine, dose dependently reduced the gth response to increasing concentrations of sgnrh. apomorph ...19902106469
distribution of gaba-immunoreactive neurons in the forebrain of the goldfish, carassius auratus.the distribution of gamma-aminobutyric acid (gaba) immunoreactivity was studied in the forebrain (tel- and diencephalon) of the goldfish by means of immunocytochemistry on vibratome sections using antibodies against gaba. positive perikarya were detected in the olfactory bulbs and in all divisions of the telencephalon, the highest density being found along the midline. in the diencephalon, gaba-containing cell bodies were found in the hypothalamus, in particular in the preoptic and tuberal regio ...199023885382
development of newly formed nephrons in the goldfish kidney following hexachlorobutadiene-induced nephrotoxicity.new nephrons developed in goldfish, carassius auratus, several weeks following hexachlorobutadiene-induced (hcbd) nephrotoxicity. basophilic clusters of presumptive nephrogenic cells incorporated 5-bromo, 2'deoxyuridine (brdu) one week after hcbd injection, indicating initiation of dna synthesis. these clusters, like renal vesicles in the developing kidney, elongated, fused with collecting ducts and developed into immature nephrons during the next 2 weeks. stereologic quantification showed the v ...19902362986
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