Publications

the effect of x-rays on chromosomes and nucleoli in ovarian eggs of the salamander, triturus pyrrhogaster.		1947	20268160
ribonucleic acid and protein in the growing oocytes of triturus pyrrhogaster.		1953	13076194
cytological observations on the epithelium of the gallbladder in urodele amphibian triturus pyrrhogaster.		1954	14356692
on the commissura postoptica in the brain of a newt, triturus pyrrhogaster.		1955	13297330
influence of ovarian extract upon the sex differentiation of terminal crest in the testis of triturus pyrrhogaster (boie).		1961	13904272
[membrane potential in kidney tubules of triturus pyrrhogaster].		1961	14496151
transmissibility and some histopathology of a spontaneously originated visceral tumor in the newt, triturus pyrrhogaster.		1963	14098909
the fine structure of tissue mast cells in triturus pyrrhogaster (boie).		1963	14046091
studies on amphibian yolk 1. the ultrastructure of the yolk platelet.	the yolk platelets of mature eggs and young embryonic cells of all amphibian species studied (rana pipiens, triturus pyrrhogaster, diemictylus viridescens, rana nigromaculata, and bufo vulgaris) have a superficial layer of fine particles or fibrils (ca. 50 a in diameter), a central main body with a crystalline lattice structure, and an enclosing membrane approximately 70 a in thickness. electron micrographs of the main body reveal hexagonal net (spacing ca. 70 a), square net (spacing ca. 80 a), ...	1963	13962448
strontium and calcium reabsorption in renal tubules of the newt, triturus pyrrhogaster.	reabsorption of calcium in the proximal tubule cannulated in vivo exceeded reabsorption of strontium. the diuretics diamox and salyrgan depressed the reabsorption of calcium but not strontium.	1964	14107462
electron microscopic examination of the sites of nuclear rna synthesis during amphibian embryogenesis.	the site of h(3)-uridine incorporation and the fate of labeled rna during early embryo-genesis of the newt triturus pyrrhogaster were studied with electron microscopic autoradiography. isolated ectodermal and mesodermal tissues from the embryos were treated in h(3)-uridine for 3 hours and cultured in cold solution for various periods before fixation with oso(4) and embedding in epon. at the blastula stage, the only structural component of the nucleus seen in electron micrographs is a mass of chr ...	1965	19866688
restitution of the eye from the iris after removal of the retina and lens together with the eye-coats in the newt, triturus pyrrhogaster.		1965	14346508
an observation of the mast cell, especially the dendrite-type tissue mast cell in triturus pyrrhogaster (boie).		1965	14289867
the origin of the luteinizing hormone-releasing hormone (lhrh) neurons in newts (cynops pyrrhogaster): the effect of olfactory placode ablation.	neurons containing luteinizing hormone-releasing hormone (lhrh) are first detected in newt embryos (cynops pyrrhogaster) in the olfactory epithelium and ventromedial portion of the olfactory nerve, after which they sequentially appear in the intracerebral course of the terminal nerve at prometamorphosis, and in the septo-preoptic area at postmetamorphosis. in adults, however, lhrh-immunoreactive cells are rarely seen in the nasal region, and their distribution shifts into the brain, suggesting t ...	1965	1423481
histochemical and electrophoretic studies of esterase in the regenerating forelimb of the adult newt, triturus pyrrhogaster.		1967	6075515
in vitro analyses of wolffian lens regeneration: differentiation of the regenerating lens rudiment of the newt, triturus pyrrhogaster.		1967	6075514
differentiation capacity of the marginal zone in the morula and blastula of triturus pyrrhogaster.		1967	6075513
the mast cells in the brain of the triturus pyrrhogaster (boie). i. the histologic studies.		1968	4181658
mast cells and histamine in a newt, triturus pyrrhogaster boié.		1968	5711878
alkaline phosphatase activity in the regenerating limb of the adult newt triturus pyrrhogaster.		1969	5384492
are the parathyroid glands necessary to the life of the newt, cynops pyrrhogaster?		1969	5395934
an electron microscopic study on the guanophore in the iris of the newt, triturus pyrrhogaster (boié).		1969	5395640
cultivation in vitro of the testis cord of the newt, triturus pyrrhogaster.		1969	5392793
behaviour of histones and cytoplasmic basic proteins during embryogenesis of the japanese newt, triturus pyrrhogaster.		1969	5408616
lymphosarcomatous disease of the newt, triturus pyrrhogaster.		1970	5538539
experiments on a spontaneously orginated visceral tumor in the newt, triturus pyrrhogaster.		1970	5278142
a nephroblastoma in a fire-bellied newt, cynops pyrrhogaster.		1970	4321086
regional histone changes in embryos of the newt, triturus pyrrhogaster, during early development.		1970	5459824
ultrasturcture of the parathyroid gland of the newt, triturus pyrrhogaster (boié) in the spring season.		1970	5468683
electron microscopic study on the parathyroid gland of the newt triturus pyrrhogaster (boié) in natural hibernation.		1970	5442608
ultrastructural change in the parathyroid gland of the phosphate treated newt, triturus pyrrhogaster (boié).		1971	5168592
[the electron microscopic study on the functional area of the digestive epithelial cell membrane in newt, triturus pyrrhogaster].		1971	5290269
electrical coupling between fat cells in newt fat body and mouse brown fat.	white fat from the newt, triturus pyrrhogaster, fat body, and brown fat from the interscapular fat pad of newborn mice have been tested for the presence of low-resistance intercellular junctions. 42 pairs of amphibian fat cells and 15 pairs of mammalian brown fat cells were found to be "electrically coupled." in most of these cases intracellular deposition of a dye, niagara sky blue: 6b, was used to supplement and confirm direct observations of impalements. coupling was often difficult to find i ...	1971	4938627
monoamine oxidase in the neurohypophysis of the newt (cynops pyrrhogaster pyrrhogaster), the toad (bufo bufo japonicus) and the tortoise (clemmys japonica).		1972	4623962
origin of histones, and relation between nuclear histones and cytoplasmic basic proteins in early development of japanese newt, triturus pyrrhogaster.		1972	5037000
self-differentiation of the heart rudiment of the newt (cynops pyrrhogaster).		1973	4797323
electron microscopic study on the parathyroid gland of the parathormone-injected newt, triturus pyrrhogaster (boie).		1973	4740812
spontaneous epidermal tumor in an adult newt, cynops pyrrhogaster.		1973	4689907
merits of the japanese newt, cynops pyrrhogaster pyrrhogaster, as an experimental animal, especially for the study of transplantation immunity.		1973	4609273
effects of growth hormone and nutrient on limb regeneration in hypophysectomized adult newts.	the effect of hypophysectomy, growth hormone (gh) and an amino acid-glucose mixture on the regenerative ability of the hypophysectomized triturus pyrrhogaster yielded the following results: 1 the survival time of hypophysectomized newts can be prolonged substantially by the sulfamide application. 2 although the limb regeneration in the hypophysectomized newt is retarded as compared with that of the pituitary intact control, it finally completes morphogenetic process under such conditions of prol ...	1973	30332863
[neural control of the terminal of the hindgut of triturus pyrrhogaster].		1974	4477310
wave of stiffness propagating along the surface of the newt egg during cleavage.	in the eggs of the newt, cynops (triturus) pyrrhogaster, change in stiffness of the cortex was measured in various regions at the time of the cleavage. measurements were performed by mitchison and swann's cell elastimeter method with a modification, in which two fine pipettes were attached to the surface of one egg at the same time, in order to compare the rigidity of two regions. the stiffness of the cortex changed very little before the start of the first cleavage. however, just before the app ...	1974	4809240
studies on the gastrulation of amphibian embryos: light and electron microscopic observation of a urodele cynops pyrrhogaster.	the course of gastrulation in embryos of a urodele, cynops pyrrhogaster, was studied with 1 mum epon sections and transmission and scanning electron microscopy. during the initial period of gastrulation, the bottle cells and a groove are formed in the dorsal part. the outer ends of the bottle cells have many microvilli, an electron-dense layer and many small vesicles. microtubules are present parallel to the long axis of the bottle cells, and a yolk-platelet-free region is observed at the inner ...	1975	1214113
[phylogenetic studies on some japanese amphibia by mean of immunoelectrophoresis. i. relationships of some frogs and newt to toad (author's transl)].	the phylogenetic relationship among toad, frogs and newt from japan was investigated by means of immunoelectrophoresis. homologous, heterologous and non-identity reactions between rabbit anti-bufo bufo antiserum and antigen from each of 13 species and 2 subspecies of japanese amphibia were examined. the number and positions of arcs appeared in these reactions were compared. the relationship observed in the comparison well coincided with the classification of the upper taxa of amphibia; viz 1) hy ...	1975	808417
cytological and microspectrophotometric analysis of mesodermalized explants of triturus gastrula ectoderm.	using isolated presumptive ectoderm of the newt (triturus pyrrhogaster) embryos as a reactor and extract of rat bone marrow as a mesodermal inductor, changes of cell number and mitotic index of the reactor cells were studied. in early stages of cultivation the increase in cell number in the mesodermalized ectodermal piece was slower than in the non-mesodermalized epidermal piece; but after 24 h it showed abrupt increase and reached a cell population equal to that of the control at 48 h of cultiv ...	1976	978130
architecture of the marrow vasculature in three amphibian species and its significance in hematopoietic development.	architecture of the bone marrow vasculature, particularly that of the femur, was analyzed in three amphibian species in relation to the early phylogeny of marrow hematopoiesis. a dye-injection method and histological techniques, including both serial sectioning and reconstruction methods, were used for this purpose. from these observations the following conclusions may be drawn. (1) marrow hematopoiesis is absent from the femur of the urodelan (triturus pyrrhogaster) and appears first in the fem ...	1976	1083670
electron microscopic stldy of the developing lateral-line organ in the embryo of the newt, triturus pyrrhogaster.	the morphological sequence of events occurring in the development of the lateral-line organ was investigated in the embryo of the newt, triturus pyrrhogaster, by means of electron microscopy. six stages of development have been defined for convenience of description. the primordium of the lateral-line organ migrating from the pre- and post-auditory placodes is segmented into a small cell mass accompanied by a few schwann cells enveloping nerve fibers. in the clump of cells of the lateral-line pr ...	1976	1008255
movement of the cell surface and change in surface area during cleavage in the newt's egg.	in cleaving eggs of the newt, cynops pyrrhogaster, the behaviour of the egg surface was analysed by observing linear and area changes in a transplanted piece of cortex which differed in pigmentation from the background. results from the animal hemisphere showed that the surface in the cleavage plane shrank extensively in the region where the early cleavage furrow was being formed. on both sides of the cleavage plane, the surface began to shrink in a direction parallel to the cleavage furrow and ...	1976	987048
the relationship of a specific chromosomal region to the development of the acrosome.	in early spermatids of urodeles the chromosome segments bearing constitutive heterochromatin are localized in one half of the round nucleus; this region becomes the basal part of the long nucleus of the spermatozoon. the euchromatic chromosome segments extend toward the anterior nuclear pole in a bouquet configuration (macgregor and walker, 1973). in the course of spermiohistogenesis, one of the heterochromatic regions (the acrosomal chromocenter) migrates from the basal part to the anterior hal ...	1976	949922
on the vascular architecture of the carotid labyrinth in cynops pyrrhogaster and onychoactylus japonicus.	the fine vascular arrangement of the carotid labyrinth in two species of urodeles, cynops pyrrhogaster and onychodactylus japonicus was investigated. india ink-gelatin injected preparations were examined under the dissecting microscope. resin casts of the blood vessels prepared using the method of murakami (1971) were observed in the scanning electron microscope. in both species, the common carotid artery terminated in the central chamber from which arose two retia mirabilia, i.e. an external ca ...	1977	597008
axon regeneration across the site of injury in the optic nerve of the newt triturus pyrrhogaster.	the process by which axons regenerate following a freeze injury to the optic nerve of the newt was analyzed by light and electron microscopy. freezing destroys cellular constituents in a one millimeter segment of the nerve, leaving intact the basal lamina and the blood supply to the eye. no axons are seen at the site of injury one to seven days post lesion. this contrasts with the persistence of normal-appearing but severed unmyelinated axons within the cranial stump which thus give a false appe ...	1977	862013
effect of starvation & hypophysectomy on amino acid levels of ovaries of triturus pyrrhogaster laur.		1978	700806
[phylogenetic studies on some japanese amphibia by means of immunoelectrophoresis. ii. relationships of some amphibians to japanese pond frogs (author's transl)].	since the japanese pond frogs (rana nigromaculata and r. brevipoda) are known to be very closely allied with each other in morphological, ecological, physiological or immunological characters, the phylogenetical relationships between the japanese pond frogs and other 10 species of japanese amphibians were investigated by means of immunoelectrophoretic analysis of liver extract. the results obtained are as follows: (1) there are conservative antigens which are commonly found in all species of anu ...	1978	631194
lh-rh neuron system of the newt by immunohistochemical study.	the location of lh-rh producing neurons, the pathways and terminal distributions of their fibers in the newt, cynops pyrrhogaster were studied immunohistochemically. the lh-rh positive perikarya are located in the nucleus of the diagonal band of broca and the medial septal nucleus. no lh-rh immunoreactive neuronal perikarya could be detected in the diencephalon. the pathways of fibers originating from the lh-rh reactive neurons were classified into three groups: the first project to the median e ...	1979	395922
role of sodium ions in p-aminohippurate transport by newt kidney.	1. the effect of external na+ concentration on p-aminohippurate uptake by isolated kidneys of newt (triturus pyrrhogaster) was studied kinetically and electrophysiologically. 2. p-aminohippurate uptake conformed to michaelis-menten type kinetics in regard to both p-aminohippurate and na+ concentrations in the incubation medium. kinetic studies revealed that reduction of na+ concentration increased the values of kt without altering the maximal rate (v) of p-aminohippurate uptake. the values of kt ...	1979	454592
cyclic changes in the cortical layer of non-nucleated fragments of the newt's egg.	various changes in the cortical layer of the amphibian egg have been observed during cleavage; for example, rounding up in the animal hemisphere, increase in stiffness of the surface and reactivity of the cortex to furrow-inducing cytoplasmic components. the three kinds of change occur synchronously with the cleavage cycle. the present experiments were aimed at determining whether the above changes in the cortical layer are caused exclusively by the nucleus or autonomously by the cytoplasm. uncl ...	1979	573307
mechanism of cleavage of newt eggs.	cytokinesis by contraction of the base of the cleavage furrow and the dependence of the position of the future furrow on the arrangement of cytoplasm under it have been demonstrated at relatively earlier stages of cleavage in amphibian eggs. the following experiments and observations on dividing eggs of the newt cynops pyrrhogaster indicated the presence of the contracting force at the base of the furrow and revealed that the above cleavage mechanisms occurred throughout cleavage. (1) deformatio ...	1979	573273
spontaneous regressive epitheliomas in the japanese newt, cynops pyrrhogaster.	spontaneous tumors in urodele amphibians have been considered uncommon, and this resistance has sometimes been associated with the natural regenerative capacity of tissues in such species. this report describes spontaneous, nonpigmented, benign epitheliomas which were found in 44 of 1586 (2.8%) adult newts, cynops pyrrhogaster, captured in central japan. both sexes were affected equally, usually with single tumors occurring at any epidermal site. under laboratory conditions, these large tumors r ...	1979	445390
occurrence of sym-homospermidine in the japanese newt, cynops pyrrhogaster pyrrhogaster.		1979	428556
studies on the formation and state of determination of the trunk organizer in the newt,cynops pyrrhogaster.	the exact localization of the presumptive trunk organizer was determined by means of vital staining at the initiation of gastrulation (0 h embryo) and subsequently in 6, 9, 12 and 24 h embryos.the progressive changes in the self-differentiation and inductive capacity of the trunk organizer were studied in isolation cultures (sitting drop) and in sandwich cultures with competent gastrula ectoderm. in the 0 and 6 h embryo cultures the excised trunk organizer predominantly formed atypical ectoderm. ...	1979	28304918
the effect of aging on the neural competence of the presumptive ectoderm and the effect of aged ectoderm on the differentiation of the trunk organizer incynops pyrrhogaster.	the effect of aging on the neural competence of the presumptive ectoderm of the early gastrula, and the effect of aged ectoderm on the differentiation of the still uninvaginated dorsal blastoporal lip at the small yolk-plug stage - representing the trunk organizer - were examined by the sandwich method incynops pyrrhogaster.the presumptive ectoderm to be used as reaction system was taken from 0 to 36 h exogastrulae obtained by operation at the early gastrula stage and combined with trunk organiz ...	1979	28304917
cell surface properties of amphibian embryonic cells.	gastrula and neurula embryos of cynops pyrrhogaster were dissociated into cell suspensions with ethylenediaminetetraacetic acid (edta), trypsin, and solution. the cells were cultured in niu-twitty's balanced salt solution and their aggregates were examined histologically. the results indicated that the capacity of amphibian embryonic cells for aggregate formation, sorting out, and notochord differentiation was not suppressed by edta and alkali treatments. trypsin treatment, however, virtually su ...	1980	6796637
[differentiation of granulocytes in the newt (triturus pyrrhogaster), with special reference to the granule formation (author's transl)].		1980	7424490
follicle-stimulating hormone (fsh) receptors in the testis of the newt, cynops pyrrhogaster, and comparison of temperature dependency of the receptors with those of the other vertebrates.		1980	6245987
electron microscope study of vertebrate liver innervation.	liver fine structure was studied in various groups of vertebrates to reveal intrahepatic nerves. nerve fibers were found in the connective tissue of the liver in all mammals, birds, and reptiles studied (japanese monkey, crab-eating monkey, rabbit, guinea pig, rat, golden hamster, pigeon, japanese quail, and turtle, pseudemys scripta). nerve fibers also made direct contact with hepatocytes in these animals except for the rat and the golden hamster. intrahepatic nerves were rare or absent in amph ...	1981	7316686
seasonal variation in pituitary gonadotropin in the adult male newt, cynops pyrrhogaster pyrrhogaster, revealed by isoelectric focusing technique and radioreceptor assay.	the seasonal variation in pituitary gonadotropin in the adult male newt, cynops pyrrhogaster pyrrhogaster was investigated by means of isoelectric focusing (ief) coupled with radioreceptor assay (rra), which employed anolis or xenopus testicular homogenates as receptors and 125i-rat fsh as radioligand. in the anolis rra system, the standard curve was obtained with 0.125-16 ng/tube of niamdd rat fsh i-3. purified preparations, chicken lh ief-1, chicken fsh agchd11113a and bullfrog basic gonadotro ...	1981	6796397
retinotopic analysis of fiber pathways is amphibians. i. the adult newt cynops pyrrhogaster.	the possibility that pathways of retinal fibers within the optic tract and the tectum of the adult newt are retinotopic was examined by selective labeling of the retinal fibers with horseradish peroxidase. within the optic tract fibers from the ventral, temporal and dorsal retinal quadrants were ordered from the dorsal to ventral edges of th optic tract. the nasal retinal fibers exhibited two different pathways. the fibers from the dorsonasal retina ran along the ventral edge of the optic tract, ...	1981	6162523
retinotopic analysis of fiber pathways in the regenerating retinotectal system of the adult newt cynops pyrrhogaster.	retinotopic analysis of the pathways of regenerating retinal fibers within the optic tract and in the tectum of an adult newt was performed by selective labeling of the retinal fibers with horseradish peroxidase. at the tenth week of regeneration, all the regenerating retinal fibers from different retinal quadrants had terminal arbors nearly at the parts of the tectum innervated normally by those quadrants. the pathways for individual retinal fibers, however, were greatly disorganized within the ...	1981	6162521
creeping locomotion of the endodermal cells dissociated from gastrulae of the japanese newt, cynops pyrrhogaster.		1981	7238592
temporal pattern of cleavage and the onset of gastrulation in amphibian embryos developed from eggs with the reduced cytoplasm.	fertilized eggs of the japanese newt, cynops pyrrhogaster, were divided into two or four equal-sized parts with fine glass rods before the first cleavage. in such cases one of the egg fragments, at least, proceeds to cleavage and gastrulates. the temporal pattern of cell division and the onset of gastrulation in such half or quarter embryos were investigated and compared with normal development. the following results were obtained: (1) desynchronization starts two divisions earlier in quarter em ...	1981	7276823
meiosis of primary spermatocytes and early spermiogenesis in the resultant spermatids in newt, cynops pyrrhogaster in vitro.	dissociated spermatogenic cells were cultivated within the collagen matrix at low cell density. the largest cell type in the culture was identified as the primary spermatocytes by their size and the morphological characteristics revealed by ultra-thin sections. chromosome analysis showed that about 90% of the cells examined were either in first or second meiosis. within the collagen matrix, the fates of 282 single primary spermatocytes at meiotic stage in diakinesis or metaphase were followed. i ...	1981	7308609
the photoreceptor cell in the pineal organ of the japanese common newt.		1982	7151960
behaviour of annulate lamellae during the maturation of oocytes in the newt, cynops pyrrhogaster.	the distribution of annulate lamellae, electron-dense masses, rough endoplasmic reticulum, and golgi complexes in longitudinal sections of newt oocytes at several stages of progesterone-induced maturation was recorded with an electron microscope equipped with a drawing device. annulate lamellae in full-grown oocytes occur in close contact with electron-dense masses and the nuclear envelope and elsewhere. stacks of annulate lamellae increase in number for 6 h after progesterone treatment. meanwhi ...	1982	7142895
effect of hypophysectomy and starvation on the fine structure of vitellogenic oocytes in the newt, triturus pyrrhogaster (laur).	hypophysectomy and starvation in triturus pyrrhogaster result in a similar ultrastructural pattern of follicular atresia. the first detectable change in the oocytes is decrease in the size and number of microvilli. subsequently the yolk precursor bodies (ypb) disappear from the micropinocytotic vesicles and the mitochondria degenerate. finally the yolk platelets undergo decomposition. the smaller yolk platelets disintegrate by granulation, vacuolation and lobule formation. the larger platelets, ...	1982	6892135
seasonal and geographical changes of spontaneous skin papillomas in the japanese newt cynops pyrrhogaster.	the occurrence of spontaneous skin papillomas in japanese newts (cynops pyrrhogaster) from niigata prefecture in northern japan was monitored over four seasons covering a period of 2 years. of 13,613 newts, 249 were found to possess papillomas. the percentage of newts with papillomas was highest in autumn, ranging from 1.93 to 5.45% of the total average. these values were more than four times as high as values obtained in the other three seasons (0.16 to 0.50%). a total of 12,167 newts were coll ...	1982	7105040
the degradation of urate in liver peroxisomes. association of allantoinase with allantoicase in amphibian liver but not in fish and invertebrate liver.	allantoinase and allantoicase were co-purified from frog (rana catesbeiana) liver. the ratio of the two enzyme activities remained constant during purification and was unchanged by a variety of treatments of the purified enzyme. these results suggest that allantoinase and allantoicase are located in the same protein. it was found that the two hepatic enzyme activities are also associated with the same protein in other frogs (xenopus laevis and rana nigromacultata), tadpoles (r. catesbeiana), and ...	1983	6833275
comparative study of extracellular fibrils on the ectodermal layer in gastrulae of five amphibian species.	previous studies have shown the presence of a network of extracellular fibrils on the inner surface of the ectodermal layer of the ambystoma maculatum gastrulae. the alignment of the network along the blastopore-animal pole axis has suggested that the network of fibrils guides the migrating mesodermal cells in gastrulae by contact guidance. we have also shown that these fibrils can be deposited on substrata by explanted embryonic fragments and that substrata conditioned in this manner support di ...	1983	6602807
seasonal changes in plasma testosterone and 5 alpha-dihydrotestosterone levels in the adult male newt, cynops pyrrhogaster pyrrhogaster.	seasonal changes in plasma levels of testosterone (t) and 5 alpha-dihydrotestosterone (dth) were examined in the adult male japanese red-bellied newt. the concentration of plasma t increased significantly (p less than 0.05) from january to february and decreased drastically from april to july when it reached its minimum. after the summer decline, plasma t increase rapidly from july to october (p less than 0.05) and reached its maximum in october. concerning the seasonal fluctuation of plasma dht ...	1983	6884270
studies on the formation and state of determination of the trunk organizer in the newt,cynops pyrrhogaster : iv. the association of the neural-inducing activity with the mesodermization of the trunk organizer.	the stepwise process of the formation and determination of mesoderm incynops pyrrhogaster was analyzed. the presumptive ectoderm (pe) of the early gastrula was transformed into mesoderm within 12 h when transplanted into the upper half of the dorsal marginal zone of the same stage. the self-differentiation capacity and the neural-inducing activity of this newly mesodermized pe (mpe) were examined by both isolation and sandwich cultures.the mpe showed self-differentiation for notochord and muscle ...	1983	28305328
the structure of the kidney of japanese newts, triturus (cynops) pyrrhogaster.	the construction of renal lobules in triturus (cynops) pyrrhogaster was studied by reconstruction from serial semithin sections, and the structure of nephrons, collecting ducts and ureters was investigated by means of light and electron microscopy. in t. pyrrhogaster the kidney was mesonephros in construction; renal lobules were arranged segmentally and each of them sent one ureter. male ureters ran caudally and met together before joining the wolffian duct. in renal lobules, long collecting duc ...	1983	6837932
studies on the development of melanophores in in vitro cultured amphibian neural plates.	various parts of neural plates of japanese newt (cynops pyrrhogaster) neurula embryos were cultured alone in drops of culture media (niu-twitty's balanced salt solution or modified leibovitz l-15 medium) with or without fetal calf serum (fcs). although none of the parts gave rise to melanophores in a medium without fcs, some produced melanophores in a medium with fcs. the localization of melanophore-producing areas in the neural plates corresponded to that of tada's (1944) findings. the assumpti ...	1983	6825926
cadmium, copper and zinc-binding protein (metallothionein) in the liver of the water lizard triturus pyrrhogaster.	a low-mr copper (cu) and zinc (zn)-binding protein was present in the liver of a control water lizard triturus pyrrhogaster. cadmium (cd) accumulated in the liver of the animals after intramuscular injections of cd salt and was bound to cu- and zn-binding protein of a single isoform that had properties characteristic of metallothionein (mt). effects of cd loading on several essential elements in the liver and kidney were also determined.	1984	6719500
fertilization of the eggs ofcynops pyrrhogaster (japanese newt) after immersion in water.	cynops pyrrhogaster oviducal eggs with and without jelly envelopes (jelly egg and dejellied egg respectively) were immersed in water, and then inseminated artificially. after 1 h of immersion in water, more than half the dejellied eggs were fertilized and developed, but no jelly eggs developed. the rapid decrease in the ability of jelly eggs to be fertilized after immersion in water is not due to a deficiency in the egg. our results make it clear that hydrated jelly envelopes prevent the eggs fr ...	1984	28305586
[evaluation of amputation techniques for the study of limb regeneration in the newt and toad].	a comparison between forelimb amputations through the radius-ulna and the humerus was made in the adult newt, cynops pyrrhogaster pyrrhogaster and the young toad, xenopus laevis. newts regenerated their forelimbs after the amputations and the new parts resembled the old in structure and function. toads regenerated their forelimbs incompletely after the amputations. the new parts lacked joints and fingers showing a simply elongate pattern. the effect of re-amputation of exposed bone on the regene ...	1984	6468505
comparative studies on the electric nature of amphibian gonadotropin.	the isoelectric focusing (ief) profiles of pituitary gonadotropic (gth) activity in six species of adult male amphibians were examined in addition to the newt and bullfrog. the gth activity was measured by two radioreceptor assay (rra) systems; one with xenopus laevis testicular homogenate as the receptor preparation, and the other with anolis carolinensis testicular homogenate, both employing 125i-labeled rat fsh as the radioligand, or by a radioimmunoassay (ria) system for bullfrog basic gth ( ...	1985	3874809
differentiation and distribution of annulate lamellae in growing oocytes in the newt, cynops pyrrhogaster.	stages of oocyte development in cynops pyrrogaster are defined, and changes of annulate lamellae in their fine structure, number, sizes and locations during oogenesis are described. the results show that two different types of annulate lamellae occur during oogenesis. one type differentiates in or at the periphery of vesicle-rich cytoplasm at the early stages of vitellogenesis and increases in number and size. the maximum number of about 40 stacks per median section of oocyte is reached at the s ...	1985	3998684
effects of temperature on papilloma growth in the newt, cynops pyrrhogaster.	the effects of temperature on skin papillomas of newts (cynops pyrrhogaster) were studied. newts bearing these tumors were maintained for 30 weeks at 4 +/- 1 (s.e.), 10 +/- 1, 13 +/- 2, 25 +/- 1, and 30 +/- 1 degree. the diameters of the papillomas were measured externally. they decreased at 4, 25, and 30 degrees, and increased at 10 and 13 degrees. the effect of temperature on the tumor growth or regression began to appear from around the 10th week. furthermore, when the temperatures were chang ...	1985	3971368
teratogenic effects of carcinogenic agents on limb regeneration in the japanese newt cynops pyrrhogaster.	normal regeneration of the amputated forelimb of the japanese newt cynops pyrrhogaster and regeneration after a single intraperitoneal injection of three potent mutagenic/carcinogenic agents was investigated. three dose levels of each agent and controls were tested for teratogenicity in this newt model with the following chemicals: n-methyl-n'-nitro-n-nitrosoguanidine (mnng), 4-nitro-quinoline-1-oxide, and 2-(2-furyl)-3-(5-nitrofuryl)acrylamide. these chemicals were administered at 10 days (late ...	1985	2866598
cell death during normal gastrulation in the newt, cynops pyrrhogaster.	cells falling off from ectoderm were observed in normally developing gastrulae of the newt, cynops pyrrhogaster, in light microscopic examination. these cells eventually died. the number of such necrotic cells per embryo varied from a few dozen to a few thousand. in embryos with many necrotic cells, the ectoderm was thin, the yolk plug large, and establishment of the neural plate was delayed compared with embryos with fewer necrotic cells. a neural tube of normal size was formed at the tail bud ...	1986	3731278
surface contraction of dividing newt eggs induced by lowering the external ionic strength or ph, or by trypsinization.	as the first cleavage progresses, newt (cynopus pyrrhogaster) eggs deprived of their vitelline membrane grow to expose the new, unpigmented surface to a saline medium full-strength steinberg solution). further exposure of these eggs to sucrose medium resulted in rapid and extensive contraction of the unpigmented surface. in the sucrose medium the contraction continued until the next cleavage, and eventually the eggs divided into many blastomeres. but partial reversal of the contraction was obser ...	1986	3793777
total dna transcription in vitro: a procedure to detect highly repetitive and transcribable sequences with trna-like structures.	total dnas from various animals were transcribed in vitro in a hela cell extract, and it was found that one to several discrete rnas were transcribed by rna polymerase iii. with tortoise (geoclemys reevessi) and newt (cynops pyrrhogaster), distinct 6.5s and 8s rnas were transcribed from these respective dnas. representative phage clones carrying the 6.5s and 8s rna genes were isolated from genomic libraries of these animals, and the sequences of these genes were determined. the 5' parts of highl ...	1986	3455763
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 ...	1986	3081602
the spike component of the fertilization potential in the toad, bufo japonicus: changes during meiotic maturation and absence during cross-fertilization.	immature oocytes of the toad, bufo japonicus, inseminated between first- and second-meiotic metaphase, exhibited polyspermy. monospermy occurred when the oocytes had reached second-meiotic metaphase. electrical recording during insemination of the immature oocyte showed fast-rising and slow-rising spikes followed by a gradual shift to a positive membrane potential. the number of fast spikes in each oocyte corresponded well with the number of sperm observed in cytological sections. mature oocytes ...	1987	3653525
induction of ocular tumor by nickel subsulfide in the japanese common newt, cynops pyrrhogaster.	chemically induced ocular tumors in amphibians have not been reported previously. in the present study, nickel subsulfide (ni3s2) was administered to lentectomized japanese common newts, cynops pyrrhogaster, by a single injection into the posterior chamber of the right eye (40-100 micrograms ni3s2/newt). control newts received a similar injection of vehicle. malignant melanoma-like tumors developed in the injected eyes of seven of eight ni3s2-treated newts at 9 months (versus none of six control ...	1987	3621207
monoamine-containing basal cells in the taste buds of the newt triturus pyrrhogaster.	monoamine-containing cells were examined by fluorescence histochemistry and electron microscopy. two or three serotonin-like fluorescent cells were located just above the basal lamina and failed to reach the free surface of the taste bud. ultrastructurally this cell type was characterized by the presence of dense-cored vesicles and finger-like cytoplasmic processes. many characteristics of merkel cells were present.	1987	3481961
autoneuralization in the amphibian ectoderm--a species-specific and stage-specific phenomenon.	ectoderm from ambystoma is especially prone to undergo 'autoneuralization'. this assertion has led to the maxim that ectoderm from this species is unsuitable for studying cell differentiation. here we report that the degree of neuralization in cultured explants is stage-dependent. control explants from blastulae (stage 8-9) show no neuralization, while explants treated with licl (10 mm) give rise to neuralization in about 70% of the cases. this difference between control and experiment decreases ...	1987	3311847
factors related to the initiation of cell migration along the inner surface of the blastocoelic wall during amphibian gastrulation.	changes in the quantity of extracellular matrix on the inner surface of the blastocoelic wall (bw) and the adhesiveness of cells to fibronectin were examined in relation to the timing of initiation of cell migration along the bw during gastrulation of the newt, cynops pyrrhogaster. extracellular matrix fibrils were already abundantly present all over the inner surface of the bw prior to the beginning of cell migration. on the other hand, the adhesiveness of cells to fibronectin rapidly increased ...	1988	3409322
formation of germ layers and roles of the dorsal lip of the blastopore in normally developing embryos of the newt cynops pyrrhogaster.	three-dimensional relationships between tissues during the formation of germ layers were studied in sections of normally developing embryos of the newt, cynops pyrrhogaster. in gastrulae, the inner postinvolution layer was not in direct contact with the outer preinvolution layer as a result of the presence of an intervening layer of cells. only after the formation of the yolk plug, a narrow strip of primitive notochord, which consisted of columnar cells, established a close contact with the cent ...	1988	3404106
na/k pump activity in the new membrane formed at first cleavage in cynops pyrrhogaster eggs.	resting membrane potentials (em) increased in the negative direction during first cleavage in cynops pyrrhogaster eggs whose new membranes formed at first cleavage were exposed to bathing solutions by removing the vitelline envelopes. em was -11.4 and -87.2 mv at the one- and two-cell stages, respectively. na/k pump activity contributed to em at the two-cell stage by about -30 mv. the distribution of na/k atpase activity was cytochemically studied by ernst's method (s. a. ernst, 1972, j. histoch ...	1988	2832229
effect of prolactin on transcutaneous na transport in the japanese newt, cynops pyrrhogaster.	the effect of ovine prolactin (prl) on the electric parameters related to active na transport across the skin was investigated in the japanese newt, cynops pyrrhogaster. spring newts living in a pond or stream for breeding and autumn newts migrating from water to land for hibernation were collected and used for the experiments. autumn newt skin was found to have a higher transepithelial potential difference (tep) and higher resistances to the active na current (rna) and to the shunt pathway (rs) ...	1988	3360287