Publications

dosage effects of the white (d) and melanoid (m) genes on pigment pattern in the mexican axolotl, ambystoma mexicanum, shaw.		1977	892230
thyroxine-induced gill resorption in the axolotl (ambystoma mexicanum).		1977	903970
a scanning electron microscopic comparison of the development of embryonic and regenerating limbs in the axolotl.	a comparison between the surface features of embryonic limb development and limb regeneration was made in the axolotl. scanning electron microscopy revealed an overall similarity between embryonic and regenerating limbs. a notable feature was the lack of a morphologically discrete apical epidermal specialization on the surface of any of the limbs. histological preparations revealed no thickening of the apical epidermis in embryonic limbs. there is a definite thickening of the apical epidermis in ...	1977	908913
cardiac mutant salamanders: evidence for heart induction.	homozygosity for gene c in ambystoma mexicanum results in no detectable heartbeat in situ. alteration of the cardiac environment through organ culture results in rapid initiation of spontaneous heartbeat, indicating that absence of cardiac function in situ is not the result of failure of embryonic induction.	1977	908918
neurophysiology of spastic, a behavior mutant of the mexican axoloti: altered vestibular projection to cerebellar auricle and area acoustico-lateralis.	the spastic mutant of ambystoma mexicanum shows deficiencies in swimming coordination and equilibrium. behavior "phenocopy" experiments done previously indicated that vestibular projections to cerebellum and hindbrain interneurons might be responsible for mutant behavior patterns. to test function in mutant vestibular projections, single unit recordings were carried out in the vestibulo-cerebellum (auricle) and hindbrain area acoustico-lateralis (aay) of wild-type and mutant animals in response ...	1977	915043
neuroanatomy of spastic, a behavior mutant of the mexican axoloti: purkinje cell distribution in the adult cerebellum.	the spastic mutant, found in the mexican axolotl, shows swimming coordination and equilibrium deficiencies. histological analyses of wild-type and spastic mutant cerebella previously characterized in physiological studies revealed changes in purkinje cell location in the mutant auricle or vestibulo-cerebellum. purkinje cells are "translocated" ventrally correlated with a similar translocation of vestibular single units described previuosly (ide, '77). where wild-type purkinje cells are distribut ...	1977	915044
genetic and experimental studies on three associated mutant genes in the mexican axolotl: st (for stasis), mi (for microphthalmic) and h (for hand lethal).	three mutant genes, st, mi, and h, were discovered in an axolotl male received from mexico city. all three are recessive to their normal alleles, and appear to segregate independently. larvae homozygous for st (for stasis) suffer blockage of the circulation at hatching or shortly after, and the majority soon die; any surviving live only a few weeks at most. the mi/mi (microphthalmic) can be identified at the feeding stage. none survives more than a few days. the h/h (hand lethals) live until the ...	1977	925667
analysis of spastic: a neurological mutant of the mexican axolotl.		1977	928456
[relationship between mitotic phases at different stages of embryonic development of axolotl].	indices and durations of mitotic phases and interphase have been determined in the axolotl embryos at the late blastula, early gastrula and mid-neurula stages. the data obtained suggest that the ratio of mitotic phases changes during embryogenesis and differs in different rudiments of the embryo at the same developmental stage.	1976	934593
[participation of irradiated tissues in the formation of limb regenerates in axolotls].		1976	939173
how x-rays inhibit amphibian limb regeneration.	the effects of an inhibiting dose of 2,000 rad of x-rays on the regenerating limbs of axolotl larvae have been examined in a histological and cytological study. particular attention was paid to the mitotic indices of normal and irradiated epidermal and blastemal cells. both the characteristic pattern of epidermal mitotic stimulation which normally follows amputation and the later increase in blastemal mitoses are suppressed by irradiation. in most cells the effects are permanent, but in a small ...	1976	939955
thin-layer isoelectric focusing of soluble and insoluble lens extracts from cataractous and normal mexican axolotl (ambystoma mexicanum).		1976	949994
protein synthesis in lethal nucleocytoplasmic hybrids between the species pleurodeles waltlii michahelles and ambystoma mexicanum shaw (urodele amphibians) obtained by nuclear grafting.	using polyacrylamide gel electrophoresis, proteins stemming from the nucleus of the donor species in nucleocytoplasmic hybrids were determined. the interspecific lethal nucleocytoplasmic hybrids of pleurodeles waltlii and ambystoma mexicanum were studied. the presence of these proteins at the blastula or early gastrula stages attests to the early nuclear control of their synthesis.	1976	965910
a staging system for forelimb regeneration in the axolotl, ambystoma mexicanum.	a staging system has been devised for normal regeneration from the upper arm in the mature axolotl. it consists of seven externally definable stages: (1) wound healing (wh): (2) dedifferentiation (dd); (3) early bud (eb); (4) medium bud (mb); (5) late bud (lb); (6) palette (pal), and (7) digital outgrowth (do). serial histological sections of 38 regenerating limbs were used to correlate gross stages with microscopic events in the regenerative process.	1976	966285
diploid gynogenesis in the mexican axolotl.	gynogenetic diploid axolotls were produced by activating eggs with ultraviolet-inactivated sperm, and then subjecting the activated eggs to heat shock. optimal conditions for ultraviolet inactivation of the sperm, and for suppression of the second meiotic division by heat shock, were established. gynogenetic diploids produced by these procedures included progeny homozygous for recessive alleles carried by a heterozygous mother. gynogenesis could, therefore, be used to uncover new mutations more ...	1976	971806
ontogeny of ldh-isozymes in mexican axolotl, ambystoma mexicanum by thin-layer isoelectric focusing.	the ontogeny of lactate dehydrogenase (ldh) isozymes in developing mexican axolotl, ambystoma mexicanum was investigated by thin-layer isoelectric focusing in polyacrylamide gel. the isoelectric points (pi values) of the isozymes were determined. the minor components generally remained masked during conventional electrophoresis, but became sharp as isofocusing progressed. we identified in developing eggs and embryos five major ldh isozymes, which could also be traced in the ovarian eggs. all the ...	1976	992242
on the determination of the dorso-ventral polarity in the amphibian embryo: suppression by lactate of the formation of ruffini's flask-cells.	cells isolated from the vegetal hemisphere of the blastula of ambystoma mexicanum differentiate spontaneously into fibroblast-like cells. similar cells may be formed from animal cells, provided they are induced either by vegetal cells or by li+. we have found that lactate and various inhibitors of rna synthesis suppress the spontaneous cell differentiation. the effect of lactate differs from that of the other agents in so far as lactate must be present before the second day of culture to suppres ...	1976	1003073
spermatogenesis and 3beta-hsdh activity in the testis of the axolotl.		2003	1012324
satellite cells in the limb musculature of the axolotl.		1976	1016334
[properties of neurons of the tectal portion of the visual system of the axolotl ambystoma mexicanum].	in the tectum opticum of the adult neotenic a. mexicanum, responses of single neuronal units to diffuse illumination and moving visual stimuli have been investigated. of 111 unites investigated, 27 are presented by tectal neurons, their maximum distribution being observed at a depth of 500-600 mu. in superficial layers 9 ipsi-elements were found; their receptive fields are located in the antero-dorsal part of the visual field, at both sides of the body axis. among the units identified as the ter ...	2007	1020556
[segregation of amphibian cns. analysis of induction process using combination experiments in ambystoma mexicanum].		1976	1023592
[differentiation tendency in mesodermal germ layer. isolation experiments on morula, blastula and gastrula stadia of axolotl (ambystoma mexicanum)].		1976	1024382
morphological and biochemical abnormalities in hearts of cardiac mutant salamanders (ambystoma mexicanum).	the effect of homozygosity for recessive gene c in ambystoma mexicanum is the absence of a heartbeat even though initially heart development appears normal. mutant embryos (c/c) are first distinguishable from their normal siblings (+/+;+/c) at stage 34 (7 days after fertilization) when the normals develop contracting hearts. the mutant hearts at this stage, upon gross examination, appear structurally normal but fail to beat. nevertheless, the mutants survive through stage 41, which is about 20 d ...	1976	1034176
regeneration-promoting properties of tribenoside in amblystoma mexicanum.	tribenoside in a dose of 100 mg/kg i.p. significantly accelerates the regeneration of puncture wounds in the caudal membrane of amblystoma mexicanum. a dose of 200 mg/kg exerts a less-pronounced vulnerary effect and is occasionally toxic. tribenoside also stimulates regeneration in this species when added to bath fluid in a concentration of 1:400,000 (exposure for 6 h daily). a concentration of 1:200,000 is less effective and has a slightly irritant effect on the tissue. 14 days after operation, ...	1976	1037626
[early activation of ribosomal rna synthesis in axolotl embryos].	the incorporation of labeled precursors (3h- and 14c-uridine) into the fractions of salt-insoluble rnas and or rrna was studied in the axolotl embryos at different stages of early development (from the end of synchronous cleavage divisions until the end of gastrulation). rna preparations isolated from the embryos at all stages studied contained incorporated radioactivity. the radioactivity of salt-insoluble rnas markedly increased at the beginning of blastulation and continued to grow, but less ...	1975	1052341
[growth of meckel's cartilage in axolotl (urodelean amphibian)].		1976	1070669
association of an ultraviolet irradiation sensitive cytoplasmic localization with the future dorsal side of the amphibian egg.	drastic alterations in neural morphogenesis can be induced by ultraviolet irradiation of the amphibian egg. the target area of u.v. was determined either by direct irradiation of various regions of the egg or by comparing the area of the u.v. hit with the location of the dorsal lip. axolotl eggs which displayed easily recognizable gray crescents were employed for the direct irradiation experiments and albino axolotl eggs were used for a comparison of the u.v. sensitivity of the animal and vegeta ...	1975	1078573
restoration of vision in genetically eyeless axolotls (ambystoma mexicanum).		1976	1082417
proceedings: the brain stem of the axolotl ambystoma mexicanum and the frog rana esculenta.		1975	1082712
apical secretion from taste bud and other epithelial cells in amphibians.	taste buds of the axolotl, ambystoma mexicanum, contain cells, previously undescribed in this species, which have a long apical process, and are similar to the type iii cells of mammalian taste buds, and to the gustatory cells in fish. in the supporting cells, there is evidence of periodic decapitation, in addition to secretion by exocytosis. bilaminar fragments, which are leaf-shaped bodies formed of two dense laminae separated by a lucent gap, protrude from the apical microvilli of the support ...	1976	1086718
studies of muscle proteins in embryonic myocardial cells of cardiac lethal mutant mexican axolotls (ambystoma mexicanum) by use of heavy meromyosin binding and sodium dodecyl sulfate polyacrylamide gel electrophoresis.	in the mexican axolotl ambystoma mexicanum recessive mutant gene c, by way of abnormal inductive processes from surrounding tissues, results in an absence of embryonic heart function. the lack of contractions in mutant heart cells apparently results from their inability to form normally organized myofibrils, even though a few actin-like (60-a) and myosin-like (150-a) filaments are present. amorphous "proteinaceous" collections are often visible. in the present study, heavy meromyosin (hmm) treat ...	1976	1107335
isozymic patterns of lactate dehydrogenase in whole embryos and adult tissues of the mexican axolotl.		1975	1109827
growth and respiration of regenerating tissues of the axolotl tail.	changes in the weight and oxygen consumption were studied during regeneration of the tail in adult axolotls and larvae. the curve of the increase in weight of the regenerating tail in both age groups is s-shaped. the intensity of respiration of the regenerating tail increases in adult axolotls and in larvae at the blastema stage; in adult axolotls there is also a second increase in the intensity of respiration of the regenerating tail during differentiation of the muscles. the relationship betwe ...	1975	1114357
hormonal stimulation as an aid to artificial insemination in ambystoma mexicanum.		1975	1116071
cell cycles in the early development of axolotl.	in axolotl embryos, during the course of development, the generation time increases, chiefly on account of a lengthening of the phase of dna synthesis, the longest in the cell cycle. at the stages of the middle blastula and early gastrula, the g1 phase is shorter than in the g2 phase, while at the neurula stage, the g1 phase is far longer than the g2 phase. cells of the chordamesoderm pass through the cycle nonuniformly during gastrulation: a period with a very low index of labeled nuclei and sl ...	1975	1124434
incorporation of labeled amino acids into proteins of the cell organelles of muscle tissue during the restoration of the regenerative capacity of the limbs of axolotl, suppressed by x-irradiation.	the incorporation of labeled amino acids into the total proteins of muscle tissue and cell organelles during the regeneration of limbs of axolotls and after the suppression of the regenerative capacity by x-irradiation and its experimental restoration were investigated. in the case of suppression of the regenerative capacity of the limbs by x-irradiation, the protein synthesis in the muscle tissue is impaired. the intensity of the incorporation of labeled amino acids into the proteins of a homog ...	1975	1129636
intracellular recordings of rod responses during dark-adaptation.	1. dark-adaptation of rod photoreceptors has been studied in the isolated axolotl (ambystoma mexicanum) retina by intracellular recordings. rod responsiveness was greatly reduced immediately after a 30 sec partial bleach, but partially recovered with time in the dark. 2. in parallel spectrophotometric measurements using isolated retinas, regeneration of the rod pigment could not be detected after a 30 sec bleach. 3. during rod dark-adaptation, the response of a rod to a given stimulus increased ...	2005	1151778
proceedings: axolotl-liver in organ culture. i. some morphological and biochemical parameters.		1975	1163296
[axolotl 1975].		1975	1164736
experimental studies on a lethal gene (1) in the mexican axolotl, ambystoma mexicanum.	1. gene ł is a recessive lethal factor found in the white strain of axolotls. animals heterozygous for the gene are phenotypically normal. when mated with each other they give offspring 25% of which exhibit the lethal effects of the gene. 2. the ł/ł homozygotes develop normally to an advanced embryonic stage (harrison stage 40) before the effects of the gene are first manifested. they then come to display a characteristic combination of abnormalities, including a disproportionately small head, s ...	1975	1167371
normal stages of development of the axolotl. ambystoma mexicanum.		1975	1167837
pathological changes of golgi complex in hemocytoblasts of spleen of young axolotls after x-irradiation.		1975	1172336
[activity and isoenzymes of lactate dehydrogenase in tissues of amphibians (xenopus laevis, ambystoma mexicanum, triturus alpestris and vulgaris) and the response in the fat body of xenopus males to gonadotropin injection (author's transl)].	lactate-dehydrogenase activity was determined by the optical test method using pyruvate as substrate and the isoenzymes were separated by vertical starch gel electrophoresis. species-specific and organ-specific characteristics of the total activity and the isoenzyme patterns of the four amphibian species are compared with those of rat and mouse. application of gonadotropin increases the amount of soluble protein and the lactate-dehydrogenase activity in the fat body of xenopus and the isoenzyme ...	1975	1176091
proceedings: development of the ipsilateral visual projection in axolotls treated with thyroxine.		1975	1177125
multiple regeneration from axolotl limb stumps bearing cross-transplanted minced muscle regenerates.		1975	1181217
inter- and intramyotomal gap junctions in the axolotl embryo.		1975	1181218
development of locomotor behavior in wild type and spastic (sp/sp) axolotls, ambystoma mexicanum.	the homozygous recessive spastic mutant found in the mexican axolotl shows violent coiling and thrashing behavior when subjected to strong tactile or electrical stimulation. in order to establish the time of onset of the first behavioral manifestation of the spastic gene, an etiological analysis of the ontogeny of swimming behavior in mutants and wild type siblings was undertaken. the locomotor patterns shown by embryos in response to an electrical stimulus were analyzed quantitatively from the ...	1975	1202151
the effects of rotation and positional change of stump tissues upon morphogenesis of the regenerating axolotl limb.		1975	1204936
[influence of environmental salinity on blood ion concentration of the intact and hypophysectomized axolotl. effect of prolactin].		1975	1205118
neural crest and early fore limb development in amphibia.	anterior trunk neural folds were exchanged between neurula stages 15 to 16 (harrison) of several triturus species and ambystoma mexicanum. donor neural crest cells migrated ventrad before and during initial bud formation. they lined the early lumb epidermis and became incorporated into the young blastema. donor melanophores and non-melanophores contributed substantially to host limb buds.	1975	1211655
[a change in the concentration of potassium and sodium during early axolotl embryogenesis].		1975	1214990
non-innervated sense organs of the lateral line: development in the regenerating tail of the salamander ambystoma mexicanum.	new lateral organs (neuromasts) are formed in regenerating tails of the larvae of a urodele, the axolotl (ambystoma mexicanum), even in the absence of the lateral line nerve, as confirmed by electron microscopic examination. the non-innervated organs are similar to normal innervated organs. the hair cells are polarized in opposite directions, and despite the lack of nerve endings, contain synaptic bodies, which in normal innervated organs are found in relation to afferent boutons.	1976	1249591
horizontal cell potentials: dependence on external sodium ion concentration.	the membrane potential of the horizontal cell of the axolotl is highly dependent on the extracellular concentration of sodium. experimental results reported here are consistent with the suggestion that in the dark the receptors release a synaptic transmitter which increases primarily the sodium conductance of the postsynaptic membrane. externally applied aspartate or glutamate depolarizes the horizontal cell membrane and eliminates the light response of the horizontal cell. however, it appears t ...	1976	1251211
low resistance junctions between mesoderm cells during development of trunk muscles.	1. electrical connexions between mesoderm cells have been examined during the formation of somites in xenopus laevis, bombina orientalis and ambystoma mexicanum. 2. in xenopus the resting potentials of presumptive myotome cells (-65 + 2 mv, s.e. of mean) and somite muscle cells (-65 +/- 0-6 mv s.e. of mean) were 40 mv, greater than dermatome cells (-25 +/- 0-6 mv, s.e. of mean). similar differences were found in bombina and ambystoma. 3. in all three species cells of the dermatome layer of the m ...	1976	1255515
alterations in resting membrane properties during neural plate stages of development of the nervous system.	1. the mean resting membrane potential of cells in the neural plate of axolotl embryos increases from -25 to -45 mv (maximum values from -35 to -60 mv) when the embryos move from early to mid-neural plate stages of development. 2. increasing the extracellular [k] to 20 mm shortly before the spontaneous increase in resting potential occurs causes neural plate cells to hyperpolarize. 3. a moderate increase in [k]omicron does not hyperpolarize the membrane of neural plate cells at earlier stages or ...	1976	1255516
mitotic activity and nucleic acid precursor incorporation in denervated and innervated limb stumps of axolotl larvae.	mitotic activity and dna and rna precursor incorporation were compared in innervated regenerating limbs and in denervated, non-regenerating limbs on days 8 and 9 post-amputation. innervated limbs had well-developed cone stage blastemas which showed high cellular mitotic indices and h3-thymidine labeling indices of 0.40-0.50 and h3-uridine labeling indices of 0.50-0.75. in contrast, denervated limbs showed dedifferentiated cells distally under thickened wound epithelia, but essentially no mitotic ...	1976	1262816
irradiation inhibits the regeneration of aneurogenic limbs.	the developing arms of axolotl larvae from the 2-digit stage onward and the aneurogenic arms of surgically denervated larvae maintained in parabiosis are able to regenerate after amputation. such regeneration is uniformly inhibited by local irradiation of the arm, whether innervated or not. this demonstration refutes a recent hypothesis that x-rays interfere with a special activity of nerves required for regeneration, and supports the earlier concept that x-rays act directly on those cells which ...	1976	1262820
the cell cycle during amphibian limb regeneration.	the duration of the cell cycle in the blastema of regenerating limbs of axolotls has been measured by means of [3h]thymidine pulse labelling and autoradiography. a chase was required to define the pulse period. an average cell cycle at 20 degrees c takes 53 h, s-phase takes 38 h; including parts of mitosis, g1 is 10 h and g2 is 5 h long. the protracted cycle and s-phase are consonant with the large genome in axolotis and other urodeles. the rapidly growing blastema probably contains a steady pop ...	1976	1270529
topological analysis of the brain stem of the axolotl ambystoma mexicanum.	the ventricular sulcal pattern and the cellular structure of the brain stem of the axolotl ambystoma mexicanum have been studied in transversely cut nissl and bodian stained serial sections. six longitudinal sulci, the sulcus medianus inferior, the sulcus intermedius ventralis, the sulcus limitans, the sulcus intermedius dorsalis, the sulcus medianus superior and the sulcus lateralis mesencephali could be distinguished. a seventh groove, the sulcus isthmi, clearly deviates from the overall longi ...	1976	1270610
retinofugal pathways in normal and albino axolotls.	the retinofugal pathways of normal and albino axolotls have been studied by tracing the transport of radioactive materials after tritiated proline was injected into one eye. the pathways demonstrated by this method include crossed projections to the diencephalon, pretectum, and tectum, and a small component that goes to the midbrain tegmentum in the basal optic root. ipsilaterally, radioactive label was found in all of the same cerebral regions, but in much smaller quantities. although on the ba ...	1976	1276914
monoclonal antibody st1 identifies an antigen that is abundant in the axolotl and newt limb stump but is absent from the undifferentiated regenerate.	monoclonal antibodies (mab) utilized in regeneration studies to date identify antigens that are up-regulated in the blastema. we obtained a monoclonal antibody, designated st1 (stump 1), that is reactive to an extracellular matrix (ecm) antigen exhibiting the opposite distribution; st1 is an abundant antigen of the limb stump soft tissues but is absent from within the blastema. the border between abundance and absence of mab st1 reactivity was sharp and extended as a concavity into the stump. th ...	1992	1279094
leydig cells in the lingual epithelium of the axolotl, ambystoma mexicanum, are immunoreactive for serotonin.	the leydig cells in the lingual epithelium of the axolotl were investigated by immunohistochemistry using serotonin antiserum. serotonin-immunoreactivity was found in their secretory granules. the physiological role of serotonin in the leydig cell, a type of exocrine cell, is unknown.	1992	1295874
melanotropin as a potential regulator of pigment pattern formation in embryonic skin.	frozen tissue sections of developing axolotl embryos were labeled by indirect immunofluorescence with anti-alpha-msh. anti-msh immunoreactivity is first detectable in embryos when neural crest cells are migrating from the neural tube. antibody labeling is visible around the lateral and ventral edges of the neural tube and in the embryonic ectoderm. as development progresses, the amount of labeling increases greatly, particularly in developing ectoderm. western blots of soluble proteins extracted ...	1992	1329074
valproic acid induced abnormal development of the central nervous system of three species of amphibians: implications for neural tube defects and alternative experimental systems.	embryos of ambystoma mexicanum, xenopus laevis, and hyperolius viridiflavus taeniatus were exposed to various concentrations of valproic acid (vpa: 0.1, 1.5, 10 mm) from blastula stage (s) 9 on up to advanced gastrulation of control embryos (s 11 1/2-12). at 10 and 5 mm vpa early development was affected in all species tested. however, the most pronounced effects occurred in ambystoma: the neural folds appeared delayed and showed a flattened and wavy shape; the neural tube was not formed and emb ...	1992	1363963
reorganization of the ependyma during axolotl spinal cord regeneration: changes in intermediate filament and fibronectin expression.	changes in intermediate filament content and extracellular matrix material showed that the injury response of ependymal cells in lesioned axolotl spinal cord involves an epithelial-to-mesenchymal transformation, and that fibrous astrocytes are excluded from the remodeling lesion site. antibody localization was used to visualize cytokeratin-, vimentin-, and glial fibrillary acidic protein- (gfap-) containing intermediate filaments, as well as the adhesive glycoprotein fibronectin. in normal axolo ...	1992	1374657
morphological features of the myenteric plexus of the stomach of the axolotl, ambystoma mexicanum, revealed by immunocytochemistry.	the general morphology of the intramural innervation of the myenteric plexus of the axolotl stomach has been investigated using antisera raised against neuron-specific enolase and a microtubule-associated protein. additionally, the occurrence of serotonin and several peptidergic neurotransmitter/neuromodulator substances was studied. immunoreactivity for galanin, vasoactive intestinal polypeptide, substance p and neuromedin u was found in both fibres and intrinsic perikarya, whereas the serotoni ...	1992	1375207
histochemical study of the heart of the axolotl (ambystoma mexicanum).	we have investigated the presence of cells containing monoamines, substance p, and neuron-specific enolase (nse) in the heart and in the pericardial wall of a urodele amphibian, the axolotl. fibers containing substance p-like immunoreactivity were present in the heart but not in the pericardial wall. also present in the heart were small branched cells, which stained metachromatically with toluidine blue. similar cells were found in the peritoneum and were tentatively identified as mast cells. ns ...	1992	1376564
evolution of vertebrate igm: complete amino acid sequence of the constant region of ambystoma mexicanum mu chain deduced from cdna sequence.	cdna clones coding for the constant region of the mexican axolotl (ambystoma mexicanum) mu heavy immunoglobulin chain were selected from total spleen rna, using a cdna polymerase chain reaction technique. the specific 5'-end primer was an oligonucleotide homologous to the jh segment of xenopus laevis mu chain. one of the clones, jha/3, corresponded to the complete constant region of the axolotl mu chain, consisting of a 1362-nucleotide sequence coding for a polypeptide of 454 amino acids followe ...	1992	1382992
selective innervation of foreign muscles following damage or removal of normal muscle targets.	the restoration of a normal pattern of neural connectivity following nerve injury depends upon the selective reinnervation of appropriate postsynaptic targets. previous studies suggest that, in the neuromuscular system, recognition between regenerating motoneurons and target muscles depends upon the positions of origin of the motoneurons and muscles. in axolotls, portions of the motor pools of adjacent muscles overlap. we found that, following removal of a pair of adjacent hindlimb muscles, ante ...	1992	1383284
isolation of lactose-binding lectins from axolotl (ambystoma mexicanum).	1. lactose-inhibitable hemagglutination activity was identified in extracts of axolotl (ambystoma mexicanum) larvae. 2. two types of lectin were isolated from extracts by affinity chromatography on lactose-sepharose. 3. a thiol-independent lectin of subunit mol. wt 15 kda and a thiol-dependent lectin of subunit mol. wt 18 kda were identified. 4. the 15 kda and a 18 kda polypeptides were weakly reactive with polyclonal anti-human galaptin serum.	1992	1424562
developmental expression of the xenopus int-2 (fgf-3) gene: activation by mesodermal and neural induction.	we have used a probe specific for the xenopus homologue of the mammalian proto-oncogene int-2 (fgf-3) to examine the temporal and spatial expression pattern of the gene during xenopus development. int-2 is expressed from just before the onset of gastrulation through to prelarval stages. in the early gastrula, it is expressed around the blastopore lip. this is maintained in the posterior third of the prospective mesoderm and neuroectoderm in the neurula. a second expression domain in the anterior ...	1992	1425349
neuron-specific enolase-like immunoreactivity in the vertebrate retina: selective labelling of müller cells in anura.	neuron-specific enolase (nse) immunocytochemistry was carried out in retinae of goldfish, axolotl, clawed frog, cane toad, lizard, chick, guinea-pig, rabbit, rat, cat and human. with the exception of anura, strong immunoreactivity was seen in the large ganglion, amacrine cells and horizontal cells of the retina in all of the other species. photoreceptors were found to be labelled in the rat and human retina and only one cone type in rabbit. photoreceptor pedicles and ellipsoids were stained in t ...	1992	1459864
reproducible proliferative responses of salamander (ambystoma mexicanum) lymphocytes cultured with mitogens in serum-free medium.	there are several reports that proliferative responses (tritiated thymidine incorporation (3htdr)) of salamander splenocytes cultured with phytohemagglutinin-p (pha) or concanavalin a (con a) in 1% fetal bovine serum (fbs)-supplemented medium are either statistically insignificant or never approach the magnitude typically observed in similarly treated cultures of frog lymphocytes. the present study confirms these findings, but also reports highly significant and reproducible pha-induced prolifer ...	1992	1473594
structural and endocytotic differences of fibroblasts and macrophages in the tail fin of amphibian larvae during metamorphosis.	different features in the fibroblasts and the macrophages, which are prominent cell types in the dermis of the dorsal tail fin of the larval axolotl, ambystoma mexicanum, and the tadpole, rana japonica, were examined by light and electron microscopy. at the non-metamorphic stages, the cytoplasm of the macrophage, loaded with numerous lysosomes, is generally located in the cell periphery. outstanding was the presence of many ruffles or microvillous projections of different shapes and sizes in the ...	1992	1482609
distribution and innervation of lateral line organs in the axolotl.	the lateral line system in axolotls consists of three types of receptors and the cranial nerves that innervate them. superficial neuromasts, which are mechanoreceptors, are distributed in lines on both the head and trunk. eight cephalic and three trunk lines can be distinguished on the basis of their innervation and differences in the orientation of the major axes of their neuromasts. a combination of histological techniques reveals that five separate pairs of cranial nerves innervate the neurom ...	1992	1484121
primary structure of neutral and acidic oligosaccharide-alditols derived from the jelly coat of the mexican axolotl. occurrence of oligosaccharides with fucosyl(alpha 1-3)fucosyl(alpha 1-4)-3-deoxy-d-glycero-d-galacto-nonulosonic acid and galactosyl(alpha 1-4)[fucosyl(alpha 1-2)]galactosyl(beta 1-4)-n-acetylglucosamine sequences.	six major neutral and acidic oligosaccharide-alditols were prepared from the jelly coat of mexican axolotl eggs. these compounds were demonstrated to contain 3-deoxy-d-glycero-d-galacto-nonulosonic acid (dnloa) and l-fucose (fuc). the structures of the six major oligosaccharides were established as follows: [sequence: see text]	1992	1499572
histological analysis of forelimb regeneration in the california newt taricha granulosa.	the regenerative ability of the forelimbs of the california rough-skinned newt, taricha granulosa was determined and compared to the same ability of the adult mexican axolotl, ambystoma mexicanum. forelimbs were amputated distally at the wrist and limbs removed at 1, 2, 3, 4, 5 and 6 weeks post-amputation were examined by histological analysis. since vitamin a and its derivatives cause extreme changes in pattern formation in the regenerating amphibian limb, we decided to study the ability of ret ...	2005	1525332
phylogeny of the third component of complement, c3: analysis of the conservation of human cr1, cr2, h, and b binding sites, concanavalin a binding sites, and thiolester bond in the c3 from different species.	the third component of complement, c3, binds to several other complement proteins. to study the diverse reactivities of c3, we analyzed the conservation of structural and functional features in the c3 from different species. first, we developed a method to purify swine (po), rabbit (rb), mouse (mo), cobra (co), xenopus (xe), axolotl (ax), and trout (tr) c3 from plasma. this involved protein precipitation by polyethylene glycol, followed by anion-exchange, gel filtration, and cation exchange chro ...	1992	1535601
thyroid hormone receptors and iodothyronine deiodinases in the developing mexican axolotl, ambystoma mexicanum.	the mexican axolotl, ambystoma mexicanum, is a neotenous salamander that rarely undergoes anatomical metamorphosis, but can be induced to do so by administration of thyroxine (t4). the neoteny appears to be due primarily to low levels of plasma t4 secondary to a low rate of secretion of thyroid-stimulating hormone. however, other factors may also be involved. in anuran amphibia, metamorphosis is accompanied by alterations in thyroid hormone receptor concentration and marked changes in the activi ...	1992	1563619
inhibition of neural crest cell differentiation by embryo ectodermal extract.	the white mutation in mexican axolotls has long been thought to be a defect associated with the embryonic extracellular environment, but not with embryonic neural crest cells. thus it was believed that pigment cells in white axolotls disappear from the skin during early development, not because they are intrinsically defective but because they have no choice but to move into an unfavorable environment. we present evidence to suggest that: (1) white neural crest cells are in fact intrinsically di ...	1992	1569410
effects of tunicamycin on retinoic acid induced respecification of positional values in regenerating limbs of the larval axolotl, ambystoma mexicanum.	urodele amphibians possess a remarkable ability to regenerate limbs following experimental or accidental amputation. since only those parts of the limb distal to the plane of amputation usually regenerate, this suggests the existence of level-specific positional values within the cells of the limb. vitamin a and other retinoids respecify the positional values of regenerating limbs such that structures proximal to the actual plane of amputation are formed in the regenerating limb producing proxim ...	1992	1581606
the marginal zone of the 32-cell amphibian embryo contains all the information required for chordamesoderm development.	the formation of the amphibian organizer is evidenced by the ability of cells of the dorsal marginal zone (dmz) to self-differentiate to form notochord and to induce the formation of other axial structures from neighboring regions of the embryo. we have attempted to determine when these abilities are acquired in the urodele, ambystoma mexicanum (axolotl), and in the anuran, xenopus laevis, by removing the mesodermalizing influence of the vegetal hemisphere at different stages of development and ...	1992	1583451
ganglia implantation as a means of supplying neurotrophic stimulation to the newt regeneration blastema: cell-cycle effects in innervated and denervated limbs.	regulation of blastema cell proliferation during amphibian limb regeneration is poorly understood. one unexplained phenomenon is the relatively low level of active cell cycling in the adult newt blastema compared to that of larval axolotls. in the present study, we used ganglia implantation as a means of "superinnervating" normally innervated adult newt blastemas to test whether blastema cell subpopulations are responsive to nerve augmentation. the effectiveness of implanted ganglia to provide n ...	1992	1583454
the stopping response of xenopus laevis embryos: behaviour, development and physiology.	1. when xenopus laevis embryos swim into an obstruction they usually stop. this stopping response to stimulation on the head is present from stage 28 to 45. at stage 37/38 it is more reliable in restrained than in free-swimming animals, and to stimuli to the cement gland than to the head skin. 'fictive' swimming also stops reliably after the same stimuli but struggling and 'fictive' struggling do not. 2. discharge of deformation-sensitive trigeminal sensory neurons in response to pressure on the ...	1992	1583603
retinoic acid-induced change in anteroposterior positional identity in regenerating axolotl limbs is dose-dependent.	retinoic acid (ra) induces pattern duplication in the proximodistal (pd) axis of axolotl limb regenerates. the effect is dose-dependent, with the maximum extent of duplication being evoked at a dose of 150 micrograms ra/g body weight. the same dose of ra induces maximum pattern completion in the anteroposterior (ap) axis of regenerating anterior half or double anterior half limbs. ra inhibits the regeneration of posterior half or double posterior half limbs (kim, w.s., and stocum, d.l. [1986] de ...	1992	1600247
the mutant axolotl short toes exhibits impaired limb regeneration and abnormal basement membrane formation.	the mutant axolotl short toes develops with abnormal kidneys, mullerian ducts, and limbs and provides one of the few experimental systems for developmental studies in amphibia. the present paper describes another deviation from this animal's normal physiology, which is very characteristic of the wild type: amputated limbs of short toes fail to regenerate. a blastema is formed but differentiation does not occur. detailed histological analysis provides evidence of abnormal formation of the basemen ...	1992	1608961
reptilian class i major histocompatibility complex genes reveal conserved elements in class i structure.	the polymerase chain reaction was used to isolate clones with class i major histocompatibility complex sequences from fish (carp), amphibian (axolotl), and two species of reptile (lizard and snake). the lizard and snake clones were used to isolate class i cdna clones. all the sequences showed the expected evolutionary relatedness. the carp and axolotl clones and one lizard cdna clone lacked the first cysteine in the alpha 3 domain which in other class i heavy chains forms an intradomain disulfid ...	1992	1612650
axonal release of transferrin in peripheral nerves of axolotls during regeneration.		1992	1614426
characterization of fibroblast growth factor binding in regenerating limb blastemas of axolotls.		1992	1614427
transient developmental expression of igy and secretory component like protein in the gut of the axolotl (ambystoma mexicanum).	we previously reported that a primitive vertebrate, the mexican axolotl (amphibian, urodela) synthesizes two classes of immunoglobulins. igm are present in serum early in the development, and represent the bulk of specific antibody synthesis after an antigenic challenge. igy occur in the serum later during the development, and are relatively insensitive to immunization. we demonstrate in the present work, using immunofluorescence with specific mabs, that igy are expressed in the gut epithelium, ...	1992	1627950
t-cell-specific membrane antigens in the mexican axolotl (urodele amphibian).	comparative analysis of sds-page patterns of axolotl spleen cells membrane detergent lysates showed important discrepancies between control and thymectomized animals. among these, a 38-kd protein band, which appeared as a major protein in controls, was not or poorly expressed after thymectomy. a rabbit antiserum (l12) raised against the 38-kd eluted band labeled in indirect immunofluorescence 80-86% of thymocytes and 40-46% of mig- lymphoid cells in the spleen. the anti-38-kd antibodies stained ...	1992	1627952
the respecification of limb pattern by new synthetic retinoids and their interaction with cellular retinoic acid-binding protein.	we describe here experiments to examine the role of cellular retinoic-acid-binding protein (crabp) during the induction of limb duplication in the chick limb bud and regenerating axolotl limb by retinoids. a newly synthesised class of retinoic acid analogues have been used because among them, some have been specifically designed with the property of binding to the retinoic acid receptors, but not to crabp. we can thus test whether binding to crabp is an obligatory step during limb respecificatio ...	1991	1655545
evidence for enkephalin- and endorphin-immunoreactive cells in the anterior pituitary of the axolotl ambystoma mexicanum.	an immunohistochemical study of opioid peptides in the hypophysis of the axolotl, ambystoma mexicanum, was carried out with antisera against leu-enkephalin, beta-endorphin, met-enkephalin, and dynorphin a (1-8). we found leu-enkephalin immunoreactivity in some fibers of the neural lobe and the median eminence. in contrast to previous reports on mammals and other vertebrates, we found leu-enkephalin immunoreactivity in many cells scattered throughout the anterior lobe. as in other vertebrates, th ...	1991	1674748
ectopic expression of a genomic fragment containing a homeobox causes neural defects in the axolotl.	an axolotl (ambystoma mexicanum) genomic fragment containing the ahox1 homeobox was placed under the control of the mouse hsp68 promoter, which seems to function constitutively in the axolotl. the resulting construct was injected into fertilized axolotl eggs to see if it would perturb development. of the injected embryos, 20% showed severe reduction of the anterior neural plate. later in development, these embryos had small heads, no eyes, and appeared to lack the normal regionalization of the b ...	1991	1680349
mhc-like molecules in some nonmammalian vertebrates can be detected by some cross-reactive monoclonal antibodies.	mab to human and mouse mhc molecules were tested for binding to blood or spleen cells of various nonmammalian vertebrates by immunofluorescence and flow cytometry. those that bound were used to immunoprecipitate cross-reactive molecules from biosynthetically or cell surface-labeled spleen or blood cells. in addition, mab to human mhc molecules were screened by western blots. as expected from the results with xenoantisera, there were few mab that cross-reacted, and many of these cross-reactions w ...	1990	1690241
heart induction in wild-type and cardiac mutant axolotls (ambystoma mexicanum).	we have re-examined some of the factors affecting the induction of heart-forming mesoderm in the axolotl. the formation of functional, rhythmically contracting myocardial tissue was used as an assay. we have found that heart-forming mesoderm is fully induced and capable of completing its developmental repertoire by the end of neurulation. as has been previously reported, pharyngeal endoderm appears to be the major inductor of heart mesoderm. unlike previous workers, we have found that the induci ...	1990	1693393
isolation and characterization of a developmentally regulated homeobox sequence in the mexican axolotl ambystoma mexicanum.	a homeobox-containing genomic dna fragment was isolated from the mexican axolotl. this clone was obtained from a partial genomic library enriched for sequences that cross-hybridized with the drosophila antp homeobox under low stringency hybridization conditions. dna sequence analysis revealed that this sequence (ahox1) was 66% homologous to the antp homeobox sequence and was most closely related to the mouse hox-1.6 (84% identity) and drosophila lab (79% identity) homeobox sequences. several cro ...	1990	1695851
an extracellular matrix molecule of newt and axolotl regenerating limb blastemas and embryonic limb buds: immunological relationship of mt1 antigen with tenascin.	several well-characterized extracellular matrix (ecm) components have been localized to the amphibian limb regenerate, but the identification and characterization of novel ecm molecules have received little attention. here we describe, using mab mt1 and immunocytochemistry, an ecm molecule expressed during limb regeneration and limb development. in limb stumps, mab mt1 reactivity was restricted to tendons, myotendinous junctions, granules in the basal layers of epidermis, periosteum (newts) and ...	1990	1696876
alkaline phosphatase and dipeptidylpeptidase iv staining of tissue components of skeletal muscle: a comparative study.	a combined alkaline phosphatase (ap) and dipeptidlypeptidase iv (dpp iv) staining reaction has demonstrated enzymatic heterogeneity of the arterial and venous segments of capillaries in rat skeletal muscle. this study compared the staining reactions of skeletal muscles in many commonly used laboratory animals, including the axolotl, chick, quail, monodelphys, rat, mouse, hamster, guinea pig, rabbit, dog, monkey, and human. dpp iv activity was found in the venous ends of the capillaries and in th ...	1990	1701462
morphology and distribution of the glossopharyngeal nerve afferent and efferent neurons in the mexican salamander, axolotl: a cobaltic-lysine study.	cobaltic-lysine complex was used to label the afferent and efferent components of the glossopharyngeal nerve in the ganglion and brainstem of the mexican salamander, axolotl (ambystoma mexicanum). the distribution of afferent cell bodies in the combined glossopharyngeal-vagus ganglion (the ix-x ganglion) was reconstructed from serial sections, and the sizes of the cell bodies were measured. the central projection of afferents and the location of efferent cell bodies were determined by the tracer ...	1990	1702112