| variable versus constant temperature acclimation regimes: effects on hemoglobin isomorph profile in goldfish,carassius auratus. | goldfish,carassius auratus, were acclimated for 2 to 3.5 weeks to three temperature regimes: [1] temporally-constant (10, 20 and 30°c), [2] diurnally-cycling (20 ± 10°c) and [3] randomly-fluctuating (± 2°c at approximately 2h intervals between extremes of 10 and 30°c). no significant differences in hematocrit were evident. hemoglobin levels in fish at constant 30°c and under randomly fluctuating temperature were significantly elevated. of the three hemoglobin isomorphs observed, the two minor co ... | 1994 | 24197140 |
| in vivo actions of a gonadotropin-releasing hormone (gnrh) antagonist on gonadotropin-ii and growth hormone secretion in goldfish, carassius auratus. | in our previous in vitro studies, [ac-delta 3-pro1, 4fd-phe2, d-trp3,6]-mgnrh (analog e) suppressed both gonadotropin-ii (gth-ii) and growth hormone (gh) release stimulated by sgnrh and cgnrh-ii. in the present study analog e significantly inhibited the increases in plasma gth-ii levels stimulated by sgnrh in sexually mature female and sexually recrudescent goldfish. treatment of goldfish with alpha-methyl-p-tyrosin methyl ester (alpha-mpt) inhibits dopamine synthesis and abolishes the inhibitor ... | 1994 | 7883150 |
| pcr-cloning of goldfish and tilapia metallothionein complementary dnas. | metallothionein (mt) is believed to be a sensitive and effective "biomarker" for monitoring metal contamination in fish. comparison of amino acid sequences between flounder mt and trout mt revealed that there is a conserved region at their n-terminals. using oligonucleotides derived from this conserved region, reverse transcription- polymerase chain reaction (rt-pcr) was performed to obtain mt complementary dnas (cdnas) from goldfish, carassius auratus, and tilapia, tilapia mossambica. these cdn ... | 1994 | 7999050 |
| phagocytotic cells in the fish heart. | comparatively little is known about host-defense activities in the fish heart. investigations showed that intraperitoneally injected carbon particles are actively taken up by the cardiac endothelial cells of the medaka oryzias latipes, but less so by those of the goldfish carassius auratus and lemon tetra hyphessobrycon pulchripinnis. (in vitro experiments confirmed these species differences in endocytic activities by these cells.) electron microscopy revealed that endothelial cells of the medak ... | 1994 | 7880594 |
| nmda receptor antagonist mk-801 blocks learning of conditioned stimulus-unconditioned stimulus contiguity but not fear of conditioned stimulus in goldfish (carassius auratus l.). | the blockade of learning of pavlovian fear conditioning by the n-methyl-d-aspartic acid (nmda)-receptor antagonist mk-801 was examined in 166 goldfish. in previously untrained fish, mk-801 blocked learning of a light-off or a tone conditioned stimulus (cs) paired with an electrical shock unconditioned stimulus (us). pretraining on the light-off cs did not affect the rate of learning of the tone cs but protected the tone learning from disruption by mk-801. switching from the light-off to the tone ... | 1994 | 7826516 |
| chromium-induced micronuclei in fish. | an investigation of the cytogenetic effects of chromium (cr(vi) and cr(iii)) in prussian carp (carassius auratus gibelio) was made. for detecting cytogenetic damage, micronuclei induction in fish erythrocyte cells was employed. fish were investigated 100 m above and 400 m below the discharge of leather waste products into the river ljubljanica, and by exposing fish to three doses of chromium (cr(vi) and cr(iii)) in the laboratory. the exposure of fish to various concentration levels (sub-lethal) ... | 2013 | 7822681 |
| temporal discrimination learning of operant feeding in goldfish (carassius auratus). | operant temporal discrimination learning was investigated in goldfish. in the first experiment, there was a fixed daily change in illumination. eight subjects were trained to operate a lever that reinforced each press with food. the period during which responses were reinforced was then progressively reduced until it was 1 hr in every 24. the final 1-hr feeding schedule was maintained over 4 weeks. the feeding period commenced at the same time each day throughout. the food dispensers were then m ... | 1994 | 16812735 |
| the in vitro metabolism of 17-hydroxyprogesterone by ovaries of the goldfish, carassius auratus, is affected by substrate concentration. | ovaries of mature goldfish (carassius auratus) were incubated with 17-[3h]hydroxyprogesterone and 0, 0.01, 0.1, 1, 10, and 100 micrograms/ml 17-hydroxyprogesterone (17p). the major products were quantified after separation by thin-layer and high-performance chromatography. the results show that substrate concentration markedly affects the pattern of metabolites. glucuronides and sulfates decreased from 7.2 +/- 2.0 and 28.5 +/- 4.4% of recovered radioactivity, respectively, in the absence of adde ... | 1994 | 7926646 |
| [the effect of cadmium on the intestine of carassius auratus]. | the paper deals with the cadmium effects on the intestinal mucosa of adult carassius auratus after 7, 14 and 40 days of exposure. after 7 days the mucosa becomes oedematous; the mucous cells show intensive secretion. the cells showing immunoreactivity for the met- and leu-enkephalin miss this feature. after 14 days these modifications diminish and after 40 days disappear completely and the mucosa gains its normal characteristics. | 1994 | 7978344 |
| immunolocalization of aromatic l-amino acid decarboxylase in goldfish (carassius auratus) brain. | the distribution of monoamines (catecholamines and serotonin) in fishes has been previously studied by immunohistochemistry of both the monoamines themselves and their biosynthetic enzymes. but the distribution of neurons containing aromatic l-amino acid decarboxylase, an enzyme involved in the biosynthesis of both catecholamines and serotonin, has up to now not been investigated. in order to improve knowledge about the localization of aromatic l-amino acid decarboxylase, neurons containing this ... | 1994 | 7913102 |
| polyunsaturated fatty acids do not activate protein kinase c in the testis of the goldfish (carassius auratus). | earlier studies have established that polyunsaturated fatty acids (pufa) such as eicosapentaenoic acid and docosahexaenoic acid inhibit steroid production in the goldfish testis. as pufa inhibit testicular steroidogenesis in the rat through activation of protein kinase c (pkc), the present studies were undertaken to characterize the properties of pkc in the goldfish testis and to test the effects of selected pufa on pkc activity. pkc activity was quantified in goldfish testis homogenate followin ... | 1994 | 24203271 |
| nearfield detection of dipole sources by the goldfish (carassius auratus) and the mottled sculpin (cottus bairdi). | surprisingly few behavioral data exist on dipole source detection by fish, despite the fact that dipole sources more closely approximate biologically relevant signals than do more nearly monopole sources such as loudspeakers, the stimulus used in nearly all fish auditory studies. in this study, dipole source detection is investigated for two fish species that differ in both their auditory and lateral line systems, the two systems capable of detecting dipole sources. conditioned suppression of re ... | 1994 | 7964388 |
| purification and characterization of p68/70, regeneration-associated proteins from goldfish brain. | two acidic proteins (p68/70) previously shown to be associated with regeneration of the goldfish optic nerve were purified 887-fold from brain homogenates of carassius auratus. purification to homogeneity was achieved by sequential chromatography of a 100,000 g brain supernatant fraction on deae-sephacel, cu(2+)-charged iminodiacetic acid agarose, and gel filtration. the stokes radius of the doublet was determined to be 5.8 nm, and the sedimentation coefficient calculated to be 5.2. from these v ... | 1994 | 8113803 |
| opioid binding in giant toad and goldfish brain. | opiate receptor expression in phylogenetically different species has played an important role in the study of opioid receptor pharmacology. total opioid binding measured with the nonselective ligand 3h-diprenorphine reveals a bmax of 21.7 +/- 1.37 fmol/mg tissue wet wt and a kd of 0.17 +/- 0.03 nm in bufo marinus (giant toad), as well as a bmax of 18.17 + 0.41 fmol/mg tissue wet wt and a kd of 0.47 +/- 0.18 nm in carassius auratus (goldfish). despite the similar levels of 3h-diprenorphine bindin ... | 1994 | 8038707 |
| melatonin signal transduction in the goldfish, carassius auratus. | generation and reception of melatonin signals in the goldfish, carassius auratus, are reviewed. the photoreceptive pineal gland of the goldfish generates circulating melatonin rhythms according to a given photoperiod under light-dark cycles and in a circadian manner under continuous dark conditions. melatonin is also produced in the retina in a similar fashion. melatonin produced in the pineal gland and retina is considered to act as internal zeitgeber in the brain and retina, respectively, cont ... | 1994 | 7708370 |
| 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 ... | 1993 | 18621254 |
| 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 ... | 1993 | 8102094 |
| 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 ... | 1993 | 24202487 |
| 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 ... | 1993 | 24202463 |
| 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 ... | 1993 | 24202457 |
| 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 ... | 1993 | 8366473 |
| 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 ... | 1993 | 8398675 |
| 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 ... | 1993 | 7683501 |
| 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 ... | 1993 | 8476383 |
| 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 ... | 1993 | 8440516 |
| 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 ... | 1993 | 8094992 |
| 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 ... | 1993 | 18816892 |
| 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 ... | 1993 | 8387165 |
| 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 ... | 1993 | 8325562 |
| 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 ... | 1992 | 1283377 |
| 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 ... | 1992 | 1332517 |
| 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 ... | 1992 | 1332498 |
| biotransformation of the flame retardant mc-984 by goldfish, carassius auratus. | | 1992 | 1421851 |
| 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 ... | 1992 | 1511892 |
| 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) ... | 1992 | 1521741 |
| cd-metallothionein in liver and kidney of goldfish (carassius auratus): effects of temperature and salinity. | treatment of goldfish with cd, by intraperitoneal injection, resulted in cd-metallothionein (cd-mt) synthesis mainly in liver and kidney. the relative amount of cd sequestered by liver metallothionein was always greater in fish maintained at 20 degrees c compared to those reared at 10 degrees c, indicating a temperature dependence of metallothionein biosynthesis; in the kidney this dependence was not so clearly evident. changes in mt levels induced by adapting fish to different salinities did no ... | 2015 | 1452441 |
| 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 ... | 1992 | 1415647 |
| the fluorescent calcium indicator indo-1/am inhibits renal proximal tubule cell volume regulation. | the intracellular calcium indicator, indo-1, is a fluorescent compound related in structure and function to the calcium chelator ethylene glycol-bis(beta-aminoethyl ether) tetraacetic acid (egta) that binds one calcium ion per molecule. in the extracellular range of 1 to 10 microm indo-1/am, the estimated intracellular concentration of the dye is 0.1 to 3 microm. therefore, it is likely that intracellular calcium signals could be blunted under these experimental conditions (cai approximately 0.1 ... | 2015 | 1503391 |
| 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 ... | 1992 | 1354419 |
| 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 ... | 1992 | 1504805 |
| 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 ... | 1992 | 1351805 |
| 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 ... | 1992 | 1515918 |
| 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 ... | 1992 | 1611875 |
| 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 ... | 1992 | 1611874 |
| 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 ... | 1992 | 1534239 |
| 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 ... | 1992 | 1319021 |
| 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 ... | 1992 | 1348678 |
| 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 ... | 1992 | 1347006 |
| 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 ... | 1992 | 1348502 |
| 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 ... | 1992 | 1644346 |
| 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 ... | 1992 | 1309572 |
| 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 ... | 1991 | 1805995 |
| 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 ... | 1991 | 1757285 |
| 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 ... | 1991 | 1682833 |
| 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 ... | 1991 | 1879667 |
| 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 ... | 1991 | 24213719 |
| 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, ... | 1991 | 24213711 |
| 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 ... | 1991 | 2035698 |
| 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 ... | 1991 | 2023929 |
| 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 ... | 1991 | 2059569 |
| 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 ... | 1991 | 2010858 |
| 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 ... | 1991 | 1874380 |
| cyclosporine inhibition of the chloride/bicarbonate exchanger of proximal renal tubules. | it has previously been reported by us that the immunosuppressant agent cyclosporine inhibits the ability of renal proximal tubule cells to regulate volume. proximal renal tubule cells exposed to hypotonic solutions rapidly swell and subsequently shrink. their regulatory cell volume decrease (rvd) is due to ca2(+)-calmodulin regulated kcl efflux followed by osmotically obligated water. in proximal renal tubule cells, potassium leaves the cell through a ca2(+)-activated potassium channel. while it ... | 2016 | 1709345 |
| 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 ... | 1991 | 1676396 |
| 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 ... | 1991 | 19912786 |
| 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 ... | 1991 | 2060686 |
| 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 ... | 1991 | 2057063 |
| 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 ... | 1991 | 1954065 |
| 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 ... | 1991 | 1752162 |
| 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 ... | 1991 | 1675973 |
| 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 ... | 1991 | 1653340 |
| 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 ... | 1990 | 2285485 |
| 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 ... | 1990 | 1963320 |
| 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 ... | 1990 | 2250337 |
| 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 ... | 1990 | 2249963 |
| 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 ... | 1990 | 2165827 |
| 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 ... | 1990 | 2143635 |
| 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 ... | 1990 | 2386727 |
| effect of ph on the accumulation kinetics of pentachlorophenol in goldfish. | the kinetics of accumulation of pentachlorophenol (pcp) at various ph values were investigated to explore how ph-dependent accumulation might influence pcp toxicity. goldfish (carassius auratus) were exposed to 5 micrograms pcp/l in a static system buffered with 7.5 mm bicine or n,n-bis(2-hydroxyethyl)-2-aminoethane sulfonic acid (bes) at ph 7.0, 8.0, or 9.0. the amount of pcp in the fish, concentration of pcp in water, and the total amount of metabolites in the system were measured after exposu ... | 2013 | 2353845 |
| acute ethanol effects on cell volume regulation. | in this work, the effects of ethanol on cellular osmoregulation were studied in isolated proximal renal tubules of carassius auratus (goldfish). in hypotonic solutions the tubule cells swell rapidly (osmometric phase) and subsequently shrink towards isotonic volumes (volume regulatory decrease phase, vrd). the osmometric phase depends on the water permeability of the cell membrane and the magnitude of the osmotic gradient. the vrd phase is complex and is a function of activation of osmotic trans ... | 2013 | 2344153 |
| 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 ... | 1990 | 2331023 |
| [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 ... | 1990 | 2382525 |
| 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 ... | 1990 | 2319013 |
| 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 ... | 1990 | 2407601 |
| 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 ... | 1990 | 2307342 |
| 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 ... | 1990 | 2106469 |
| 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 ... | 1990 | 23885382 |
| 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 ... | 1990 | 2362986 |
| breakdown of the sperm nuclear envelope is a prerequisite for male pronucleus formation: direct evidence from the gynogenetic crucian carp carassius auratus langsdorfii. | the gynogenetic fish, carassius auratus langsdorfii (the ginbuna, a crucian carp), provides an interesting model for the study of the mechanisms controlling male pronucleus formation. when the sperm nucleus of a different subspecies (c. a. cuvieri) is incorporated into the gynogenetic egg, the nuclear envelope of the spermatozoon is not broken down, and the pronucleus fails to develop, although dispersion of the sperm chromatin occurs to some extent within the space limited by the nuclear envelo ... | 1990 | 2295362 |
| nonmammalian vertebrate models in studies of brain-steroid interactions. | estrogen formation in brain and pituitary mediates certain androgen actions in central targets. goldfish (carassius auratus) and quail (coturnix coturnix japonica) have been advantageous for studying the role of locally formed estrogen in autoregulating aromatization and in controlling estrogen receptor occupancy, androgen receptor levels, and behavioral expression. data from these two experimental models reveal a molecular basis for androgen-estrogen synergism in neuroendocrine tissues and for ... | 1990 | 1974804 |
| telencephalic function implicated in food-reinforced color discrimination learning in the goldfish. | the effects of telencephalic ablation on the learning of color discrimination were studied in the goldfish (carassius auratus) to determine the role of the telencephalon in the learning. the performances of normal and telencephalonless animals were compared in relation to their instrumental training rates. the animals were trained to discriminate between blue and green stimulating patches presented simultaneously. normal and telencephalonless animals which underwent ten trials per day were unabl ... | 1989 | 2602497 |
| cyclosporine nephropathy: inhibition of osmoregulatory renal cell transport. | the immunosuppressant agent cyclosporine (sandimmune) is a calmodulin inhibitor that has potent nephrotoxic properties. recently, it has been observed that osmoregulation in the proximal tubules of the bony fish carassius auratus (goldfish) is a calmodulin-regulated cell function. as their mammalian counterparts do, these renal tubule cells swell when exposed to hypotonic solutions. this is followed by a slower volume regulatory decrease phase owing to kcl efflux and osmotically obligated water. ... | 2015 | 2802513 |
| the temporal evolution of masking and frequency selectivity in the goldfish (carassius auratus). | the temporal evolution of masking and frequency selectivity was studied in the goldfish using classical respiratory conditioning and a tracking psychophysical procedure. the temporal position of a brief tonal signal within a longer duration, tonal masker has little or no effect on signal detectability when the frequency of the masker is less than or equal to that of the signal. for masker frequencies above that of the signal, signal detectability improves as the signal onset is delayed relative ... | 1989 | 2794245 |
| bifurcation analysis of nonlinear retinal horizontal cell models. i. properties of isolated cells. | 1. bifurcation theory is used to study properties of nonlinear analytical and computational models of isolated retinal horizontal cells. the analytical model is based on the published data of shingai and christensen describing steady-state i-v characteristics of horizontal cells isolated from catfish (ictalurus punctatus) retina. the computational model is based on i-v characteristics of distinct macroscopic membrane currents observed in horizontal cells isolated from goldfish (carassius auratus ... | 1989 | 2769357 |
| eurythermic and stenothermic growth of cultured fish cells and their thermosensitivity. | rbcf-1 cells derived from the caudal fin of the goldfish (carassius auratus) have been established at 37 degrees c, and could grow at a wide range of temperatures (20-37 degrees c). to examine the mechanism(s) of this eurythermic property, we isolated clones from rbcf-1 cells with different optimal growth temperatures. r37 clone grew continuously at 37 degrees c but could not grow at 27 degrees c. r27 clone grew continuously at 27 degrees c but could not grow at 37 degrees c. thus r37 and r27 ce ... | 1989 | 2606945 |
| day-night rhythms of shoaling behavior in goldfish: opioid and pineal involvement. | intracerebroventricular (icv) administration of the opioid peptide, beta-endorphin (5.0 pg/g) to goldfish, carassius auratus, significantly increased the cohesiveness and duration of shoaling ('bout' length) in shoals of five fish, as well as decreasing the latency of shoal formation in response to an external disturbance, while a higher dose of beta-endorphin (15 pg/g) decreased shoaling. there were day-night rhythms in shoaling and in the extent of the facilitatory effects of beta-endorphin (5 ... | 1989 | 2532372 |
| trh stimulates the release of pomc-derived peptides from goldfish melanotropes. | the release of immunoreactive (ir) alpha-msh and ir acth from goldfish (carassius auratus) melanotropes was investigated using superfused isolated dispersed neurointermediate lobe cell columns. stimulation of neurointermediate lobe cell columns with pulses of trh evoked dose-dependent increases in the concomitant release of ir alpha-msh and ir acth. reversed-phase high performance liquid chromatography (rp-hplc) was used to characterize the alpha-msh and acth immunoreactivities released from a n ... | 2013 | 2555798 |
| involvement of steroid hormones in the preovulatory gonadotropin surge in female goldfish. | goldfish,carassius auratus, spawn several times within a spawning season. a gonadotropin (gth) surge occurs at the time of ovulation in this cyprinid species. this ovulatory gth surge mediates the processes of final oocyte maturation and ovulation, and occurs at the end of each spawning cycle. within a cycle, there is a shift in the predominant plasma steroid from estradiol to testosterone, and finally 17α, 20β-dihydroxy-4-pregnen-3-one at the time of the ovulatory gth surge. high levels of test ... | 1989 | 24221765 |
| hypothalamic peptides influencing growth hormone secretion in the goldfish,carassius auratus. | in vivo andin vitro techniques were used to examine the influence of various vertebrate peptides on growth hormone (gh) secretion in the goldfish. tetradecapeptide somatostatin (srif-14) was found to inhibit gh secretionin vitro from perifused pituitary fragments, whereas similar concentrations of a salmonid srif peptide (ssrif-25) did not affect gh secretion from the goldfish pituitary fragments. this indicates that srif receptors on the goldfish pituitary are very specific for srif-14-like pep ... | 1989 | 24221764 |
| neuropeptides regulating the activity of goldfish corticotropes and melanotropes. | the goldfish (carassius auratus) has proven an advantageous model for investigations of the neuroendocrine regulation of pituitary hormone secretion in teleost fishes. investigations examining the secretion of adrenocorticotropin (acth) and melanocyte-stimulating hormone (msh) from pituitary cellsin vitro have been used to identify neuropeptides influencing goldfish corticotrope and melanotrope activity. ovine crf, urotensin i (ui), arginine vasotocin (avt), isotocin and angiotensins i and ii st ... | 1989 | 24221751 |