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research on cholesterol, steroidal hormones and liposoluble vitamins by thin layer chromatography in some adipose organs of anuran amphibians. ii. liposoluble vitamins.by means of thin layer chromatography and selective detection, vitamin a acetate, vitamin e and vitamin e acetate, vitamin d3 and cholesterol were identified in the prepericardic body, adrenal tissue, fat bodies and testis of bubo bufo, as well as in the prepericardic body of rana esculenta. on the contrary, liposoluble vitamins could not be isolated from the adipose tissue occurring in the thoracic cavity of rana esculenta, or in bufo bufo muscles. the results are discussed in correlation with ...1976218524
[concentrating ability of the gallbladder: a comparative study in some vertebrate species (author's transl)].the bile salts, chloride, sodium, potassium and nitrogen content of the gallbladder bile was studied in goat, sheep, cattle, pig, rabbit, dog, monkey (erythrocebus patas), chicken, lizard (lacerta ocellata), frog (rana esculenta), trout (salmo gardnieri) and barbel (barbus barbus). a significant correlation was found between bile salts and sodium (positive), chloride and sodium (negative) and chloride and bile salts (negative). the gallbladder concentrating ability was very high in monkey, lizar ...1975808839
[a molecular hybrid having gonadotropic activity in frogs composed of the alpha subunit of bovine luteinizing hormone and a subunit of a gonadotropin of a teleost fish].the alpha subunit of bovine lh and the subunit su ii of carp gonadotropin are able to associate. the hybrid is about one hundred times less active than c-gth or b-lh, respectively on goldfish and rat ovarian adenyl cyclase. however it is more efficient than both horomones on an amphibian (rana esculenta), on spermiation in vivo as well as on ovarian adenyl cyclase in vitro.1976816536
synthesis and intracellular transport of proteins in the exocrine pancreas of the frog (rana esculenta). ii. an in vitro study of the transport process and the influence of temperature.frog pancreatic tissue was pulse-labelled in vitro with 3h-leucine and protein transport was studied in exocrine cells by electron microscope autoradiography. the proteins appeared to be synthesized in the rer and transported to the secretory granules along a similar route and with the same velocity as previously described under in vitro conditions. evidence was obtained for the involvement of the vesicular and tubular elements at the periphery of the golgi system in transferring protein from th ...19761083293
aluminium localization in amphibian skin with the electron microprobe and ion microanalyzer.emp and ima studies show the presence of a1 in the epidermis of larvae and young adults of discoglossus pictus and rana esculenta, which disappears during later stages of development. a1 is practically absent in the epidermis of xenopus laevis and pleurodeles waltlii. the localization of a1 with emp and ima supports the biochemical results. the function of a1 in the epidermis is not known at present.19761083571
[regeneration of the crystalline lens in anuran amphibia in the postembryonal stage. experimental excision of the crystalline lens in rana esculenta and xenopus laevis larvae]. 19761088056
müller (glial) cells in the retina of urodeles and anurans reveal different morphology by means of freeze-fracturing.müller (glial) cells of the retina of various species of amphibia (urodeles and anurans) were investigated by means of the freeze-fracture technique. this was done because müller cells in anamniotes were believed to differ from those in mammals in that they should lack the so-called orthogonal arrays of particles (oap) which are a characteristic feature of müller cells in mammalian retina. however, as we could demonstrate previously (berg-von der emde and wolburg, glia, 2 (1989) 458), fish retin ...19921407671
study of frog (rana esculenta) proopiomelanocortin processing in the intermediate pituitary. identification of alpha-melanotropin, beta-melanotropin, lys-gamma-melanotropin, and corticotropin-like intermediate lobe peptide.the proteolytic processing of frog (rana esculenta) proopiomelanocortin in melanotropic cells of the intermediate pituitary gland has been examined through purification of the mature fragments by reverse-phase high-pressure liquid chromatography and microsequencing of isolated peptides. alpha-melanotropin, beta-melanotropin, lys-gamma-melanotropin, corticotropin-like intermediate lobe peptide, and hinge peptide have been isolated and chemically characterized. the results show a high preservation ...19911651291
the effect of clofibrate on amphibian hepatic peroxisomes.liver peroxisomes of two anuran amphibian species, rana esculenta and xenopus laevis, were studied in untreated and in clofibrate-treated adults by means of complementary technical approaches, ie, ultrastructural cytochemistry, cell fractionation and marker enzyme activity assays. in untreated adults, hepatic peroxisomes were found to be very scarce in xenopus when compared to rana. activities of catalase, d-amino acid oxidase and of the three first enzymes of the peroxisomal beta-oxidation syst ...19911681969
functional expression of urea channels in amphibian oocytes injected with frog urinary bladder mrna.in amphibian urinary bladder epithelium, vasopressin increases passive urea permeability, concomitant with the appearance of a facilitated urea transport. amphibian oocytes from xenopus laevis and rana esculenta were microinjected with total or fractionated poly(a+) rna isolated from frog urinary bladder epithelial cells. after several (3-5) days at 18 degrees c, the urea flux was assayed by measuring the uptake and efflux of [14c]urea in water-injected and mrna-injected oocytes. a 2 to 3-fold i ...19911715756
distribution of galanin-like immunoreactivity in the brain of rana esculenta and xenopus laevis.the immunocytochemical distribution of galanin-containing perikarya and nerve terminals in the brain of rana esculenta and xenopus laevis was determined with antisera directed toward either porcine or rat galanin. the pattern of galanin-like immunoreactivity appeared to be identical with antisera directed toward either target antigen. the distribution of galanin-like immunoreactivity was similar in rana esculenta and xenopus laevis except for the absence of a distinct laminar distribution of imm ...19911719037
effects of gonadotropin-releasing hormone variants on plasma and testicular androgen levels in intact and hypophysectomized male frogs, rana esculenta.the effects of vertebrate gonadotropin-releasing hormone (gnrh) variants on plasma and testicular androgen level in intact and hypophysectomized (pdx) male frogs, rana esculenta, have been investigated. in intact animals, mammalian (m)-gnrh, m-gnrh analog (buserelin), salmon (s)-gnrh, chicken (c) i-gnrh, cii-gnrh, d-arg6-cii-gnrh (cii-gnrha), and lamprey (l)-gnrh (1.5 micrograms and 6 micrograms, total dose given on alternate days for 5 days) were able to enhance androgen production showing that ...19921729384
carnosine in the brain and olfactory system of amphibia and reptilia: a comparative study using immunocytochemical and biochemical methods.the pattern of distribution of carnosine-like immunoreactivity and its relation to glial fibrillary acidic protein immunoreactivity have been studied in two lizards (gallotia galloti and tarentola delalandii) and in two anuran amphibians (rana esculenta and xenopus laevis) using immunocytochemical techniques. biochemical data obtained by paper electrophoresis show that the dipeptides carnosine and homocarnosine are both present in the brain of all the species examined. in the central nervous sys ...19911795878
day and nighttime concentrations of 5-methoxytryptophol and melatonin in the retina and pineal gland from different classes of vertebrates.5-methoxytryptophol (ml) and melatonin concentrations were determined by radioimmunoassay in the retinae and pineal glands of frogs (rana esculenta), chickens (gallus domesticus), quails (coturnix coturnix), and european hamsters (cricetus cricetus), killed in the afternoon (1500-1700 hr) and around midnight (2400-0200 hr). ml was only detectable in significant amounts in the frog retina. in the pineal gland ml levels showed the opposite profile to retinal ml, with measurable levels in the chick ...19911808021
immunoreactive melanocyte-stimulating hormone (alpha-msh) in the brain of the frog (rana esculenta l.). 1978206484
amplitude and frequency fluctuations of spontaneous otoacoustic emissions.amplitude and frequency fluctuations of spontaneous otoacoustic emissions have been studied. spontaneous otoacoustic emissions were recorded from eight human ears and two frog ears (rana esculenta). record length typically was 80 s. for a recorded emission signal, the amplitude signal a(t) (average a0) and time intervals t(ti) between successive positive-going zero crossings (i counts zero crossings) were determined. emission amplitude and period both showed small fluctuations: delta arms/a0 ran ...19902262634
purification and subcellular localization of zn-dependent acid p-nitrophenylphosphatase in frog liver and comparison with other vertebrates.zn2(+)-dependent acid p-nitrophenylphosphatase (zn-acpase) from liver of rana esculenta was purified to homogeneity. the purified enzyme moves as a single electrophoretic band at ph 8.3 in 7.5% acrylamide and was coincident with the enzyme activity. the enzyme has a molecular weight of 102,000 +/- 5,000d and is a dimer with two apparently similar polypeptide chains of 48,000 +/- 3,000d as determined by sodium dodecylsulfate gel electrophoresis. zn-acpase from frog liver requires zn2+ ions for ca ...19902161444
neuromedin b-like immunoreactivity in the brain of the green frog (rana esculenta l.).three rabbit polyclonal antisera, originally developed against neuromedin b and highly selective against ranatensin subfamily molecules, were used to study the distribution of neuromedin b-like immunoreactivity in the brain of rana esculenta. immunopositive cell bodies were observed in several brain regions, including medial and lateral septal nuclei, nucleus of the diagonal band of broca, medial amygdala, ventral striatum, ventromedial and posterior thalamic nuclei, nucleus of the periventricul ...19911801930
[adaptative differential maturation of neurohypophyseal provasotocin in amphibians: presence of hydrin 2(vasotocinyl-glycine) in anura but not in urodela].occurrence of hydrin 2 (vasotocinyl-glycine), an intermediate in the provasotocin processing, has been shown in the neurointermediate lobe of the pituitary of semi-aquatic or terrestrial amphibian species belonging to the order anura, namely rana esculenta, r. temporaria, r. pipiens (ranidae), and bufo bufo, b. marinus, b. ictericus (bufonidae). in contrast hydrin 2 appears absent in species belonging to the order urodela, namely the axolotl ambystoma mexicanum (ambystomidae) and the pleurodele ...19911756409
retino-retinal projections in three anuran species.in juvenile and adult xenopus laevis, in adult bufo marinus and rana esculenta frogs retino-retinal projections were traced by filling the central stump of one optic nerve, cut 2-3 mm from the eye, with horse-radish peroxidase (hrp) or cobaltic-lysine complex (clc). the presence of retino-retinal projections was confirmed in all 3 species both in the juvenile and the adult. up to 12 ganglion cells per retina were found to be filled retrogradely with hrp together with optic axons filled anterogra ...19892510094
a gonadotropin releasing hormone analog induces spermiation in intact and hypophysectomized frogs, rana esculenta.the sperm-releasing activity of a gonadotropin releasing hormone (gnrh) agonist, buserelin (gnrh) and hypophysis homogenate (pd) preparations was studied in intact and hypophysectomized (pdx) frogs, rana esculenta. in addition, human chorion gonadotropin (hcg) was tested in pdx animals, and gnrh antagonist (gnrha) treatments were carried out in intact and pdx animals, in combination with the hormonal injections. gnrh or pd treatments were able to elicit spermiation in intact and pdx animals. whi ...19892513222
genome exclusion and gametic dapi-dna content in the hybridogenetic bacillus rossius-grandii benazzii complex (insecta phasmatodea).among sicilian stick insects, two hybridogenetic complexes have been discovered: bacillus rossius-grandii benazzii and b. rossius-grandii grandii, which also produce androgenetic offspring. the egg maturation of the former is analyzed here through dapi fluorometry, which, besides the assessment of the meiotic stages, also allows their dna measurements and the analysis of sperm-head evolution into male pronuclei in these polyspermic eggs. hybridogenetic eggs undergo an extrasynthesis of chromosom ...19921449790
preparation and characterization of troponin c from bullfrog skeletal muscle.troponin c was isolated from the skeletal muscle of bullfrog (rana catesbeiana), and its relative molecular mass was estimated to be 18,000 by sds/polyacrylamide gel electrophoresis. in its amino acid composition, bullfrog troponin c was similar to that of the frog (rana esculenta) but different from that of rabbit. its ultraviolet spectrum was consistent with its amino acid composition. the ultraviolet difference spectrum of the ca(2+)-loaded form vs. the metal-free form indicated that the sing ...19921295889
the amino-acid sequence of the most acidic major parvalbumin from frog muscle.the primary structure of the most acidic (pi - 4.50) of the two major parvalbumins from frog (rana esculenta) has been determined from a study of its trypsic peptides and of overlapping peptides generated by limited trypsic digestion, chymotrypsic digestion and n-bromosuccinimide cleavage of the protein. the amino acid sequence so obtained is considered in comparison with those known for other parvalbumins and for rabbit troponin-c.19751080707
hydrins, hydroosmotic neurohypophysial peptides: osmoregulatory adaptation in amphibians through vasotocin precursor processing.from neurointermediate pituitary glands of xenopus laevis and rana esculenta, previously unreported peptides termed hydrins, active on water permeability of frog urinary bladder and frog skin (brunn or "water-balance" effect), have been isolated and sequenced. these peptides seem to be derived from the pro-vasotocin-neurophysin precursor. hydrin 1, found in xenopus, has been identified as vasotocin c-terminally extended with the gly-lys-arg sequence; hydrin 2, found in rana, has been identified ...19892787509
[melanotropic hormone in the green frog (rana esculenta): biochemical and radioimmunological study].the alpha-msh levels in the frog hypophysis were measured by use of a sensitive ans specific radioimmunoassay. sephadex g-50 gel chromatography of frog pars distalis and pars intermedia extracts showed that frog hypophyseal msh was chemically related to synthetic alpha-msh. rat tissue homogenates were capable of degrading frog pars intermedia msh as well as synthetic alpha-msh. these results provide evidence that the frog hypophysis--pars intermedia and pars distalis--contains an alpha-msh-like ...1976827375
[life cycle of the trematode echinostoma caproni richard, 1964 (echinostomatoidea) (author's transl)].the life cycle of the trematode echinostomatoidea echinostoma caproni richard, 1964, develops under natural conditions in madagascar in a bird falco newtoni and in a gastropod biomphalaria pfeifferi. metacercaries encyst in other molluscs and in the kidney of an amphibian ptychadaena mascareniensis. the cycle has been reproduced experimentaly in france. the defivitive hosts are the white mouse, the rat and the chick. biomphalaria galbrata is the first and the second intermediate host. metacercar ...1978697289
lack of effect of rat atrial natriuretic factor (ranf) on the renal function in frogs.1. the aim of the present experiments was to examine the question whether the rat atrial natriuretic factor (ranf 1-28) could alter the fractional excretion of sodium (fena) and other solutes in the frog (rana esculenta). 2. although experiments were performed throughout the year possible seasonal changes in the animals were considered in particular. 3. in all frogs, a hypotonic diuresis was induced. 4. under these conditions in winter frogs, the control fena was 8.8 +/- 5.8% (15) [means +/- sd ...19882901317
[differences in macroglia of the spinal cord in various cold-blooded and warm-blooded animals].certain macroglial differences of the spinal cord in poikilothermal (rana esculenta, lacerta agilis) and in homoiothermal (columba livia, felis domesticus, macaca rhesus) animals have been revealed. a greater amount of glial satellites, surrounding neurons, motor centers of the spinal cord and appearance of new variety of astrocytes and oligodendrocytes are observed in the homoiothermal animals. it is supposed that the phenomenon mentioned indirectly reflects the evolutionary process of a more d ...19902275612
[radioimmunologic assay of plasma corticotropin in the green frog, rana esculenta l].in the green frog (rana esculenta) the plasma contains a polypeptide immunologically related to human and porcine corticotropins. a radiommunoassay capable of detecting 4.10-12 g hog acth has been used for a direct plasma acth assay in the frog. using this method, the acth rate was determined both in untreated frogs and in animals under various experimental conditions.1975167995
mauthner neurons survive metamorphosis in anurans: a comparative hrp study on the cytoarchitecture of mauthner neurons in amphibians.giant medullary neurons were revealed in adult xenopus laevis and rana esculenta following hrp injections to the spinal cord. these neurons were identified as mauthner neurons because (1) they have the same position and orientation as the larval mauthner neurons, i.e., they lie at the level of the viiith nerve root. (2) they have two large dendritic trees that for each species are similar to those of the larval mauthner neurons, (3) they are clearly distinguishable from other large reticular neu ...19863081602
comparative study of tyrosinases from different sources: relationship between halide inhibition and the enzyme active site.the inhibition of tyrosinases from frog epidermis (rana esculenta ridibunda), mushroom (agaricus bisporus) and harding-passey mouse melanoma by halides is compared. in all cases, the inhibition is ph dependent, increasing when the ph decreases. the order of inhibition is i- greater than br- greater than cl- much greater than f- for frog epidermis tyrosinase, f- greater than i- greater than cl- greater than br- for mushroom tyrosinase and f- greater than cl- much greater than br- greater than i- ...19863082587
[interpretation of the cross sectional structure of skeletal muscle fibers. 2. light and electron microscopic studies of m. rectus abdominis in rana esculenta].in both longitudinal and cross sections of rectus abdominis muscle of rana esculenta three types of muscle fibres are identified by means of light and electron microscopy. a comparison is made between these fibre types in homologous muscles of frog and mammals (rat and mouse). in longitudinal sections of mammalian and frog muscle the z-line can be used for discrimination of the fibre types a, b and c because that line is of different thickness in each type. the proportions of the thickness in fr ...1975137606
thymosin beta 4xen: a new thymosin beta 4-like peptide in oocytes of xenopus laevis.two new thymosin beta 4-like peptides have been detected in ovaries of xenopus laevis and rana esculenta. previously, it was reported that thymosin beta 4 can be found in various species, from mammals to amphibians, e.g., in x. laevis [s. erickson-viitanen, s. ruggieri, p. natalini, and b.l. horecker (1983) arch. biochem. biophys. 221, 570-576]. however, oocytes and spleen from r. esculenta contain no thymosin beta 4 but a similar peptide without methionine. the peptide from r. esculenta elutes ...19883124756
preparation of specific antiserum against rana esculenta pre-alpha lens crystallin.specific antiserum against rana esculenta lens pre-alpha crystallin was prepared in a rabbit by injecting antigen-antibody precipitate of this crystallin obtained from immunoelectrophoresis of esculenta total soluble lens proteins against homologous antiserum.197660253
the neural retina of the frog contributes a slow cornea-positive potential to the electroretinogram.a c-wave-like cornea-positive potential in the isolated rabbit retina has been described. in this study, frog retinas were investigated to see if the neural retina contributes a slow cornea-positive component to the c-wave of the electroretinogram. the eye cups of both rana esculenta and rana temporaria exhibited a normal electroretinogram with c-wave, a larger proximal light-induced extracellular potassium increase, a small distal extracellular potassium increase and an extracellular potassium ...19921633749
dihydrofolate reductase activity in the purkinje neuron populations of some non-mammalian vertebrates.the intensity and distribution of histochemically demonstrable dihydrofolate reductase (fh2-r ec 1.5.1.3.) in unfixed cryostat sections was studied in purkinje neurons of adult vertebrates that have either simple neural circuits and cytoarchitectonics (ictalurus nebulosus, rana esculenta) or complex neural circuits and cytoarchitectonics (coturnix coturnix japonica), compared with the rat as a control. the reaction was generally undetectable in ictalurus nebulosus and in rana esculenta; with pos ...19883149438
species differences in the stereoselectivity of kappa opioid binding sites for [3h]u-69593 and [3h]ethylketocyclazocine.stereoselectivity of the binding sites for the specific kappa-opioid agonist [3h]u-69593, a benzeneacetamido based ligand was investigated in membrane suspension prepared from frog and rat brain, as well as guinea pig cerebellum, using the pure chiral forms of different unlabelled opiates. the ligand binding sites showed stereospecificity with at least three orders of magnitude differences in the affinities (measured as ki values) of the opioid stereoisomer pairs both in rat and guinea pig membr ...19921331638
[morphological and physiological characterization of fiber types in the iliofibular muscle of rana esculenta].in both longitudinal and cross sections of the m. iliofibularis of rana esculenta three types of muscle fibres are identified by means of light and electron microscopy. these fibretypes called a-, b- and c-fibres are according to the fibres of m. rectus abdominis of the frog. they can be compared with the fibres of the m. rectus abdominis of rat and mouse. but there is another distribution of the fibretypes a, b and c in the m. iliofibularis and in the m. rectus abdominis. the m. iliofibularis i ...1977308746
macrophage disappearance reaction in rana esculenta induced by specific antigen and rabbit lymphokines.macrophage disappearance reaction was induced by intraperitoneal injections of specific antigens in rana esculenta sensitized by bovine gamma globulin and mycobacterium bovis bcg. rabbit lymphokines derived from concanavalin a stimulated blood lymphocytes injected intraperitoneally were able to induce macrophage disappearance reaction in normal rana esculenta. this suggests that mammalian lymphokines are capable of acting in amphibia. mammalian lymphokines have not an exclusive class-specificity ...197773345
histochemical demonstration of nadph-diaphorase activity in the pineal organ of the frog (rana esculenta), but not in the pineal organ of the rat.using the histochemical method for the demonstration of nadph-diaphorase activity, the pineal organ of the frog and rat was investigated in serial sections. a positive nadph-diaphorase activity was demonstrated in pinealocytes and nerve cells in the pineal organ of the frog, but not in the rat. an intense activity existed in the apical portion of the photosensitive pinealocytes of the frog. large nadph-diaphorase positive nerve cells (15-20 microns in diameter) were located within the parenchyma ...19902372437
[the reaction of tadpoles of the common toad (bufo bufo l.) to chemical signals from individuals of their own and other species].in behavioral experiments, toad tadpoles-recipients chose between two parts of test aquarium with chemical signals of donor tadpoles of the same or different (rana esculenta) species. the youngest studied tadpoles (43-45 stages) preferred the part of the aquarium with chemical cues from sibs as compared to non-sibs. no reliable difference in "non-sibs: water" system was observed. in "tadpoles of the same species: tadpoles of the other species" system, recipient tadpoles chose "their" part of the ...19892515677
isolation of terminal cisternae of frog skeletal muscle. calcium storage and release properties.sarcoplasmic reticulum (sr) terminal cisternae (tc) of frog (rana esculenta) fast-twitch skeletal muscle have been purified by isopycnic sucrose density gradient centrifugation. biochemical characteristics and ca2+ release properties have been investigated and compared to those of the homologous fraction of rabbit skeletal muscle tc. the frog sr fraction obtained at the 38/45% sucrose interface appears to be derived from the terminal cisternae region as judged by: (a) thin section electron micro ...19882968342
[differences in the cyto- and angioarchitectonics of the ventral horns of the spinal cord in higher and lower vertebrates].when comparing structures of the ventral horns of the spinal cord in amphibia (rana esculenta) and carnivora (cat, dog), it has been stated that in the latter, together with increasing number of neurons their blood supply is improving. this is demonstrated as a growing density of the capillary network in the cerebral substance and increasing number of capillaries within 25 mcm around the neuronal bodies. glial surrounding of the neurons changes considerably. both in the amphibia and carnivora as ...19873501280
comparative studies on the nonprotein but nondialysable sugar-peptide fraction isolated from the plasma of various classes of vertebrates.1. the nonprotein but nondialysable ninhydrin-positive substances isolated from plasma of some species belonging to four classes of vertebrates (fishes, amphibians, birds and mammals) were studied. 2. in all species studied (cyprinus carpio, salmo gairdneri, rana esculenta, rana temporaria, gallus domestica and rattus rattus) a similar group of nondialysable ninhydrin-positive substances may be isolated from the plasma by sephadex g-25 filtration followed by dialysis. 3. thin-layer sephadex g-25 ...1977318251
phylogenesis of mast cells. i. mast cells of the frog rana esculenta. 19704101012
thyrotropin-releasing hormone does not alter the release of melanocyte-stimulating hormone or adrenocorticotropic hormone from the rat pars intermedia.thyrotropin-releasing hormone (trh) has been reported to stimulate the release of melanocyte-stimulating hormone (msh) from the pars intermedia (pi) of rana esculenta. to test its effect on the rat pi, acutely dispersed rat pi cells, as well as whole nervosa-intermedias (ni), were incubated with synthetic trh, from 10(--10)--10(--4)m. trh did not alter the release of either msh or adrenocorticotropic hormone (acth).1977204881
[comparative electrophysiologic study of the motor and sensory myelinized nerve fibers in rana esculenta and xenopus laevis]. 19674234703
luteinizing hormone-releasing hormone as a potent stimulator of the thyroidal axis in ranid frogs.plasma concentrations of t4, measured by radioimmunoassay, were raised significantly 2 and 4 hr after intravenous injection of synthetic luteinizing hormone-releasing hormone (lhrh) in rana ridibunda (1 and 10 micrograms on 2 consecutive days) and in rana esculenta (10 micrograms). a dose of 1 microgram lhrh was not so effective as 50 micrograms synthetic thyrotropin-releasing hormone (trh) when injected in rana ridibunda in november. however 10 micrograms lhrh was equipotent to 50 micrograms tr ...19883133281
the effect of mammalian gonadotropins and homologous gonadotropins on the activity of delta 5-3 beta-hydroxy-steroid-dehydrogenase (hsd) in hypophysectomized rana esculenta.mammalian gonadotropins and partially purified gonadotropins (fsh and lh) from an amphibian (rana esculenta) were used to investigate their action on enzymatic activity of delta 5-3 beta-hsd in male and female hypophysectomized rana esculenta in stage of genital activity (october) and in stasis or hibernation stage (january). amphibian and equine lh stimulate delta 5-3 beta-hsd activity especially in females hypophysectomized in the stage of genital activity, while ovine fsh action is very low a ...197945831
the rate of action of tetrodotoxin on myelinated nerve fibres of xenopus laevis and rana esculenta.1. the experiments were done on single ranvier nodes of xenopus laevis (voltage clamp) and rana esculenta (action potentials). rate and size of the effect of tetrodotoxin were determined by the reversible reduction of either the sodium inward current (xenopus) or of v(a), the maximum rate of rise of the action potential (rana).2. the results of tetrodotoxin block at equilibrium could be excellently fitted by assuming a one-to-one reaction between toxin molecules and sodium channels of the xenopu ...19734543328
[research on the behavior and the fate of the metacercaria of ascocotyle branchialis j. timon-david 1961 (trematoda, digenea, heterophyidae) during metamorphosis of the host (rana esculenta l.)]. 19664956427
[microcirculation and pigmented cells in rana esculenta, cavia cobaya and macacus rhesus studied in vivo and with the electron microscope]. 19684975267
[a mutation of rana esculenta: black-eyed frog]. 19704991536
lampbrush and mitotic chromosomes of the hemiclonally reproducing hybrid rana esculenta and its parental species.mitotic chromosomes of the european water frogs rana ridibunda and rana lessonae, the parental species of rana esculenta, differ significantly in their centromeric regions: when c-banded or when made fluorescent, the centromeres of r. ridibunda (and of ridibunda chromosomes in r. esculenta) are visible as a conspicuous dark granule or as a conspicuous fluorescent spot; the centromeres of r. lessonae (and of the lessonae chromosomes in r. esculenta) are inconspicuous or not fluorescent. lampbrush ...19902391468
characterization of gonadotropin-releasing hormone (gnrh) binding sites in the pituitary and testis of the frog, rana esculenta.frog, rana esculenta, pituitary and testis gonadotropin-releasing hormone (gnrh) receptors were characterized by using 125i-chicken iignrh (ciignrh) as radiolabeled ligand. at 4 c equilibrium binding of 125i-ciignrh to pituitary homogenates was achieved after 90 min of incubation; binding of 125i-ciignrh to testis membrane fractions reached its maximum at 60 min of incubation. binding of the radioligand was a function of tissue concentration, with a positive correlation over the range 0.5-2 tiss ...19902161225
effect of vasopressin on the permeability of non electrolytes across the skins of rana esculenta and bufo bufo.maximal doses of vasopressin increase the permeability of the skins of bufo bufo and rana esculenta to urea, ethylene glycol, glycerol, erythritol, beta-alanine, leaving virtually unmodified that of mannitol and antipyrine. these results demonstrate that the response to vasopressin is quite different in amphibian skins as compared to the bladders. a careful analysis of the effects of vasopressin on non-electrolyte permeability as a function of their molecular weight demonstrates that hormone eli ...19852412508
morpho-functional study of hypothalamic neurosecretion. iv. the effect of osmotic stress on the preoptico-neurohypophysial system of rana esculenta, rana temporaria, and xenopus laevis. 19705493990
distribution of renal calcitonin binding sites in mammalian and nonmammalian vertebrates.calcitonin (ct), the hypocalcemic hypophosphatemic hormone, is present in many vertebrate species. the principal target organs for ct are, in mammals, kidney and bone, and in fish, bone and gill. we have investigated the presence of renal calcitonin binding sites in a fish (salmo gairdneri), two amphibians (bufo bufo and rana esculenta), two reptiles (pseudemys scripta and gekko gecko), and two birds (gallus domesticus and cothurnix japonica). we compared their distribution to a mammal, the rat ...19892555248
the ultrastructure of gliosomes in the brains of amphibia.small fragments of superficial neuropil and fragments of deeper layers from various regions of the brains of xenopus laevis daud. and rana esculenta l. were fixed in buffered osmium tetroxide, embedded in vestopal w or methacrylate, and studied with the electron microscope. the glial fibers and their meningeal end-feet contain numerous large mitochondrion-like dense bodies for which the term "gliosome" has been adopted. gliosomes have a specific and constant structure characterized by the presen ...19655865926
high energy phosphate utilization for work production and tension maintenance in frog muscle.frog (rana esculenta, l.) gastrocnemii (161 pairs) or sartorii (8 pairs) were stimulated by intermittent tetani at 10 degrees c (20 hz, supramaximal intensity, n2 atmosphere) isometrically (im) or isotonically (it) for various durations (6-30 s) at different tensions (0.05-1.00 po = maximal im tension at resting length, lo). the energy expenditure (e) was measured from atp and phosphocreatine breakdown and the high energy phosphate equivalent of lactic acid production. both in im and it conditio ...19883263619
ultrastructural analysis and cholinesterase activity in the brain capillaries of bufo bufo and rana esculenta.we have investigated the structure and the cholinesterase features of the brain capillaries in two adult amphibians (rana esculenta and bufo bufo). we found that brain capillaries are un-fenestrated and the endothelial cell edges are joined by tight junctions. the brain capillaries in both species are characterized by high levels of ache. this enzyme is only localized in the basal membrane, whereas we have found the reaction product neither in the endoplasmatic reticulum nor in the golgi apparat ...19873121723
[on melanokinesis of internal ear pigmented cells in rana esculenta and cava cobaya. hormonal and ultrastructural studies]. 19666012355
preparation and characterization of the major isotype of parvalbumin from skeletal muscle of the toad (bufo bufo japonicus).the major isotype of parvalbumin has been isolated from the skeletal muscle of the toad, bufo bufo japonicus. unlike the skeletal muscle of every frog so far examined (rana esculenta, rana temporaria, and rana catesbeiana), which contains two major isotypes of parvalbumins, toad skeletal muscle has been shown to contain only one isotype, but the content of parvalbumin in toad skeletal muscle was similar to the sum of those of the two isotypes in skeletal muscles of frogs. this feature of toad sk ...19873125161
characterization of kappa 1 and kappa 2 opioid binding sites in frog (rana esculenta) brain membrane preparation.the distribution and properties of frog brain kappa-opioid receptor subtypes differ not only from those of the guinea pig brain, but also from that of the rat brain. in guinea pig cerebellum the kappa 1 is the dominant receptor subtype, frog brain contains mainly the kappa 2 subtype, and the distribution of the rat brain subtypes is intermediate between the two others. in competition experiments it has been established that ethylketocyclazocine and n-cyclopropylmethyl-norazidomorphine, which are ...19902177154
sensory cells of the "rod-" and "cone-type" in the pineal organ of rana esculenta, as revealed by immunoreaction against opsin and by the presence of an oil (lipid) droplet.the pineal organ of the frog, rana esculenta, was studied by use of light- and electron-microscopic methods including immunoreaction against opsin. most of the morphologically classified cone-type outer segments of the pineal photoreceptors reacted with antisera against opsin of the bovine retina that is dominated by rods. some of the outer segments of pineal photoreceptor cells remained unstained in accord with the reference tissue, the frog retina, where generally the rods were opsin-positive ...19853158392
deduced amino acid sequence and e1-e2 equilibrium of the sarcoplasmic reticulum ca(2+)-atpase of frog skeletal muscle. comparison with the ca(2+)-atpase of rabbit fast twitch muscle.the cdna encoding a ca(2+)-transport atpase of frog (rana esculenta) skeletal muscle was isolated and characterized. the deduced amino acid sequence, consisting of 994 residues, showed 89% identity to the fast twitch muscle sarcoplasmic reticulum ca(2+)-atpases of chicken and rabbit. northern blot analysis using a fragment of this cdna as probe detected a 5.0 kb message in frog skeletal muscle but did not detect any mrna encoding sarcoplasmic reticulum ca(2+)-atpase in frog cardiac muscle. the e ...19921386027
molecular forms of immunoreactive gonadotropin-releasing hormone in hypothalamus and testis of the frog, rana esculenta.the hypothalamus and the testis of the frog, rana esculenta, contain gonadotropin-releasing hormone (gn-rh)-like peptides which are recognized by an antiserum raised against mammalian gn-rh. two molecular forms which coelute with synthetic chicken ii and salmon gn-rh from reverse-phase hplc were distinguished in the hypothalamus. a single peak coeluting with synthetic chicken ii gn-rh was present in the testis.19892676699
an amphibian two-domain 'big' neurophysin: conformational homology with the mammalian msel-neurophysin/copeptin intermediate precursor shown by trypsin-sepharose proteolysis.a 'big' frog (rana esculenta) neurophysin, encompassing sequences homologous to mammalian msel-neurophysin and copeptin, has been passed through a trypsin-sepharose column in order to compare its conformation with that of the two-domain intermediate precursor isolated from guinea pig. whereas the polypeptide possesses 8 arginine residues, only two cleavages were observed located in a putative inter-domain sequence (at arg-94 and arg-114). because free vasotocin has been isolated from the frog, i ...19883258254
immunoreactive opsin in the pineal organ of reptiles and birds.the presence of opsin was investigated with light microscopic immunocytochemistry in pinealocytes of reptiles and birds (emys orbicularis, pseudemys scripta elegans, lacerta agilis et viridis, gallus domesticus, columba livia, melopsittacus undulatus, serinus canaria, taeniopyga punctate). the outer segments of pinealocytes selectively bound antiopsin antibody as revealed by indirect immunocytochemical techniques, indicating the occurrence of a rhodopsin-like photopigment in these structures. th ...19826213109
cerebrospinal fluid-contacting neurons, sensory pinealocytes and landolt's clubs of the retina as revealed by means of an electron-microscopic immunoreaction against opsin.opsin-immunoreactive sites of hypothalamic cerebrospinal fluid (csf)-contacting neurons, pinealocytes and retinal cells were studied in various vertebrates (carassius auratus, phoxinus phoxinus, triturus cristatus, bombina bombina, rana esculenta) by means of postembedding immuno-electron microscopy with the use of the protein a-gold labeling method. the retina of the rat served as a general reference tissue for the quality of the immunocytochemical reaction. a strong opsin immunoreaction (rat-a ...19836226359
isolation and characterization of acylneuraminate cytidylyltransferase from frog liver.frog liver (rana esculenta) is a rich source of acylneuraminate cytidylyltransferase. the soluble enzyme was purified 250-fold almost to purity with 25% yield and a specific activity of 9 mkat/kg protein (0.54 u/mg protein) using deae sephadex and sepharose 6b chromatography, followed by preparative polyacrylamide gel electrophoresis. the molecular weight of the cytidylyltransferase was determined to be 163 000 with the aid of sepharose 6b chromatography and gel electrophoresis, with or without ...19806253375
[thyroid homeostasis in animals with iodine deficiency].the content of total iodine, its hormonal and nonhormonal fractions as well the level of protein-bound iodine in blood and basic tissue targets in representatives of 4 classes of animals: esox lucius l., rana esculenta, streptopelia decaocto priv., lepus europaeus pall. inhabiting the mountain regions with iodine deficiency in environment and in the lowlands of transcarpathia with higher iodine provision have been investigated. a considerable decrease of general and hormone iodine level in the a ...19883265636
antagonistic actions of prostaglandins e2 and f2 alpha on the isolated lungs of the frog, rana esculenta l.isolated lungs of the frog, rana esculenta l., when incubated in amphibian ringer solution for 30 min, produced a prostaglandin e2-like substance (27.1 +/- 3.8 ng/g w.w.), as determined by bioassay on the isolated rat stomach strip. the release of pge2-like substance from skin, heart and bowel is also reported. the activity of synthetic prostaglandins e2 (pge2) and f2 alpha (pgf2 alpha) on the muscular contractility of frog isolated lungs was investigated: pge2 and pgf2 alpha relaxed and contrac ...19872885133
effects of physostigmine on the voltage dependent ionic conductances of skeletal muscle fibres.the voltage dependent ionic conductances were studied by analysing the phase plane trajectories of action potentials evoked by electrical stimulation of the sartorius muscles of the frog (rana esculenta). the delayed outward potassium current was measured also under voltage clamp conditions on muscle fibres of either the frog (rana esculenta) or xenopus laevis. on analysing the effect of physostigmine decreasing the peak amplitude, the rate of both the rising and falling phases of the action pot ...19836316728
a gonadotropin-like thermostable peptide, prepared from bovine anterior pituitary, inducing spermiation in the frog rana esculenta (l.) and binding to a rat ovarian fsh receptor.a thermostable peptide, inducing sperm release in rana esculenta l. and having immunological properties which resemble those of the gonadotropins but nonidentical with any one of the gonadotropins or their subunits, has been prepared from pars distalis of bovine anterior pituitaries by means of acetic acid extraction, heating, ethanol precipitation, and reverse-phase high-performance liquid chromatography (hplc). during the purification, the biological activity was regularly followed by means of ...19853000863
thyroid hormone feedback regulation of the secretion of bioactive thyrotropin in the frog.thyrotropin-releasing hormone (trh), ovine corticotropin-releasing hormone (ocrh) (both 268 nm), and mammalian gonadotropin-releasing hormone (mgnrh) (268 and 2680 nm) stimulated the secretion of bioactive thyrotropin (tsh) by rana esculenta pituitaries (pars distalis) in vitro. preincubation of the pituitaries with 50 ng/ml (64 nm) thyroxine (t4) for 6 hr suppressed the trh- and ocrh-induced (268 nm) secretion of bioactive tsh, but did not affect the response of the pituitaries to 268 nm mgnrh. ...19921490587
light- and electron-microscopic demonstration of immunoreactive opsin in the pinealocytes of various vertebrates.an antibody to opsin isolated from rod outer segments of the frog retina was applied in light- and electron-microscopic immunocytochemical studies to the pineal organ of various vertebrates (cyprinus carpio, carassius auratus, rana esculenta, emys orbicularis, pseudemys scripta elegans, lacerta agilis and viridis. gallus domesticus, columba livia, melopsittacus undulatus, serinus canaria, taeniopyga punctata, didelphis virginiana, erinaceus roumanicus, myotis myotis, rabbit, rat, cat).19816458362
a comparative study on glyoxalase ii from vertebrata.s-2-hydroxyacylglutathione hydrolase (glyoxalase ii) from the liver of animals belonging to the various vertebrate classes (oryctolagus cuniculus, gallus gallus, python molurus, rana esculenta, esox lucius) have been purified from 100,000 g supernatants of liver homogenates, using acetone fractionation and affinity chromatography. subsequent comparative studies were concerned with some molecular and kinetic properties. isoelectric focusing gave evidence for a single form of liver glyoxalase ii i ...19873495432
[effect of human chorionic gonadotropin on the gonads of rana esculenta in organotypic culture, during metamorphosis]. 19715316985
[comparison of the growth rate of the hypophysis of a amphibian (rana esculenta) with that of a mammal (domestic albino mouse)]. 19761088463
purification and physical properties of arginase from xenopus laevis.arginase from the liver of xenopus laevis has been purified to homogeneity by heat treatment, acetone fractionation, and isoelectric focussing. the main component had an isoelectric point (i.e.p.) of 7.3; there is a minor component of i.e.p. 7.8. the molecular weight of the enzyme, as determined by gel filtration on sephadex g200, is 76,000 daltons, substantially less than that of rat liver arginase studied concurrently. the molecular weight of the subunits, as determined by electrophoresis in s ...19827130924
comparison of the pineal complex, retina and cerebrospinal fluid contacting neurons by immunocytochemical antirhodopsin reaction.the presence of rhodopsin was investigated by an indirect immunocytochemical method in the pineal complex of various vertebrates (carassius auratus, cyprinus carpio, hypophthalamichthys molitrix, lucioperca lucioperca, triturus vulgaris, bombina bombina, rana esculenta, pseudemys scripta elegans, lacerta agilis et viridis, white leghorn chickens, rat), in the retina of lebistes reticulatus, lucioperca lucioperca, rana esculenta, lacerta agilis, pseudemys scripta elegans, the chicken and the rat, ...19807456628
sequence and functional expression of an amphibian water channel, fa-chip: a new member of the mip family.a new member of the family of water channel proteins (aquaporin-chip) related to the major intrinsic protein (mip) family is described. the cdna coding for this amphibian chip was cloned from frog (rana esculenta) urinary bladder, a model for the kidney collecting duct, using a rt-pcr cloning strategy. the encoded protein, designated fa-chip (frog aquaporin-chip), shows 77.4%, 42.4% and 35.6% identity with the three proteins now referred to as the aquaporins of the mip family, i.e., human chip28 ...19947515688
[immunobiology of poikilothermic vertebrates. vi. dynamics of antibody producing cells in lymphoid organs of the frog rana esculenta l]. 19715316814
[the nature of urea transport across the skin of of rana esculenta].in several epithelial tissues such as toad bladder, gallbladder and human red cells, it has been established that urea movement implies a phloretin sensitive mediated transport. in the skin of the toad bufo viridis also it has been described an active transport of urea. our data, obtained on the frog skin seem to demonstrate the existence of some specific mechanism for urea transport towards the inside solution. in fact, two molecules having the some molecular diameter, such as urea and thiourea ...19826980654
tyrosine aminotransferase activity of frog (rana esculenta) liver--ii. comparative aspects of intracellular distribution.1. a subcellular fractionation procedure for frog liver is reported and validated by the distribution pattern of several marker enzymes, also in comparison with rat liver. 2. the subcellular distribution of tyrosine aminotransferase was investigated in frog liver as compared to rat liver: a different distribution of the enzyme was observed, being the activity mostly recovered in mitochondrial and cytosolic compartments. 3. results indicate that mitochondrial tyrosine aminotransferase of both fro ...19826129941
invertebrate and vertebrate immune cells express pro-opiomelanocortin (pomc) mrna.we show here that hemocytes and leukocytes with phagocytic activity from both invertebrates (planorbarius corneus, viviparus ater) and vertebrates (carassius auratus, rana esculenta) express pro-opiomelanocortin (pomc) mrna, as assessed by in situ hybridization with a digoxigenin-labeled human dna probe. these data are in accord with previous observations from our laboratories on the presence in these cells of pomc-derived peptides and strongly suggest that these molecules--highly conserved thro ...19957620207
[experimental transmission of trematoda into ducks (anas platyrhynchus domesticus) by means of tadpoles of rana esculenta]. 19715317241
the gonadotropin-releasing hormone (gnrh) neuron system of the clawed toad xenopus laevis.the gnrh immunoreactive (gnrh-ir) neuronal system of the clawed toad xenopus laevis was studied and compared with the gnrh-ir system of the frog rana esculenta. polyclonal antibodies against mammalian (mgnrh) and chicken type-ii gnrh (cgnrh-ii), and monoclonal antibodies against mgnrh were used in the study. in the xenopus laevis, most of the immunopositive neuronal cell bodies were located in telencephalic (35-50 per cent) and diencephalic areas (50-65 per cent). about 15-20 per cent of the gnr ...19947725831
antimicrobial peptides from amphibian skin: an overview.over the past three decades, numerous peptides have been isolated from amphibian skin secretions. many of these peptides were shown to be homologous to hormones and neurotransmitters of mammals. in recent years it has been shown that these secretions also contain a multitude of antimicrobial peptides. most of these peptides are positively charged and have a propensity for forming an amphipathic helix. other types of peptides have been detected as well, including one group which contain d-allo-is ...19947768159
mechanical work, oxygen consumption, and efficiency in isolated frog and rat muscle.the total work done during shortening, in repeated stretch-shortening cycles and the subsequent recovery oxygen consumption were measured in isolated frog (rana esculenta) sartorius at 12 degrees c and rat (wistar strain) extensor digitorum longus (edl) and soleus at 20 degrees c. two procedures were followed. in the first, the muscles were lengthened in the relaxed state and stimulated isometrically just before and during the first part of shortening. the peak efficiency (positive work done div ...19873496797
vasoactive intestinal polypeptide (vip)-like immunoreactivity in anuran intestine.immunocytochemical and radioimmunological techniques with region specific antisera have been used to identify a vasoactive intestinal polypeptide-like material in the anuran intestine. seven species of anura were investigated: bombina bombina, alytes obstetricans, rana temporaria, rana esculenta, hyla arborea, hyla crepitans and bufo bufo. in five of the species (a. obstetricans, r. temporaria, h. arborea, h. crepitans and b. bufo) vasoactive intestinal polypeptide-like immunoreactive mucosal en ...19816784927
[3h]dynorphin1-8 binding sites in frog (rana esculenta) brain membranes.opioid binding sites specific for [3h]dynorphin1-8 were characterized in the particulate membrane fraction of frog (rana esculenta) brain. the degradation of the radioligand during the assay was prevented by the use of a broad spectrum of peptidase inhibitors. the binding of [3h]dynorphin1-8 to frog brain membranes was stereoselective, reversible, saturable, and displaceable by a series of opioid ligands including dynorphin1-13, bremazocine, levorphanol and naloxone. the specific binding of [3h] ...19947915022
[the gametokinetic reaction in male amphibia. i. weight changes of the testicles of rana esculenta l. in vivo caused by injection of human chorionic gonadotropin]. 19655896421
the contralaterally projecting neurons of the isthmic nucleus in five anuran species: a retrograde tracing study with hrp and cobalt.the morphology of projection neurons of the isthmic nucleus was studied in rana esculenta, r. nigromaculata, bufo marinus, b. bufo gargarizans, and xenopus laevis from a comparative anatomical point of view. the main point of this work was to provide an anatomical basis for electrophysiological studies. neurons projecting to the ipsilateral optic tectum were labeled by retrograde transport of horseradish peroxidase and cobaltous lysine complex injected into the optic tectum. contralaterally proj ...19947962721
serosal and mucosal facilitated transport of urea in urinary bladder of of bufo bufo: evidence for an alleged water uptake.in bufo bufo urinary bladder an urea facilitated transport has been localised on the luminal membrane. the transport fulfils the criteria for such a mechanism, i.e. is saturable and is inhibited by phloretin, a specific inhibitor for urea transport. similarly to that of bufo marinus and rana esculenta the luminal membrane of bufo bufo urinary bladder shows an adh stimulated facilitated transport. experiments wtih amphotericin b, serosal phloretin (with and without adh), have demonstrated the pre ...19836135534
ganglionic blocking effect of indomethacin and other prostaglandin synthetase inhibitors.the effect of various prostaglandin (pg) synthetase inhibitors such as indomethacin, diclofenac, fenoprofen, niflumic acid and sulindac was studied on the isolated sympathetic ganglion of rana esculenta. it was found that all the tested drugs inhibited synaptic transmission, an effect related to the inhibition of pg synthetase. it has been suggested that pgf2a might be involved in the modulation of synaptic function in the frog sympathetic ganglion.19806258388
comparative studies on the astrocytic reaction in the lesioned central nervous system of different vertebrates.the morphology of the optic nerve of fish, amphibians, reptiles, birds and mammals, with special reference to the membrane architecture of the astrocytes, is described by means of ultrathin sections and freeze-fracture replicas. the reaction patterns of the astrocytes in response lesions of the optic nerve are discussed with respect to the regenerative capacity of the central nervous system (cns). astrocytic membranes in the optic nerve of the goldfish and rana esculenta do not reveal orthogonal ...19873624861
two gnrhs fluctuate in correlation with androgen levels in the male frog rana esculenta.chickenii-(cii-) and salmon (s-) gnrh levels have been measured in the male frog rana esculenta during the annual cycle. the presence of pituitary binding activity for both peptides and plasma androgen levels has been investigated in order to give insight into the significance of the dual control exerted by the gnrh forms present in the r. esculenta brain. chickenii- and s-gnrhs showed high values during the spring-summer period. conversely, while cii-gnrh peaked in february, s-gnrh declined slo ...19938354991
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