Publications

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[effect of aldosterone on uridine incorporation in acid-soluble and ribonucleic fractions of bufo marinus bladder]. 19694184344
effect of adenohypophysectomy on salt and water metabolism of the toad bufo marinus with studies on hormonal replacement. 19695779821
teleostean urophysis: stimulation of water movement across the bladder of the toad bufo marinus.an effect of material from the caudal neurosecretory system of a teleost on the isolated toad bladder is described. urophysial breis from gillichthys mirabilis result in dose-related water movement across the bladder. as little as one one-hundredth of a urophysis induces a threefold increase in osmotic water movement.19695765109
pharmacological studies of the cardiovascular system in the anaesthetized sleepy lizard (tiliqua rugosa) and toad (bufo marinus). 19695777379
the bladder of bufo marinus as an excretory organ for potassium. 19695350363
tolerance limits of the toad, bufo marinus, in south florida. 19705440928
microbodies (peroxisomes) in the toad, bufo marinus. a cytochemical study. 19704989401
copper in hepatocyte lysosomes of the toad, bufo marinus l. 19705460017
neurohypophyseal hormone-sensitive adenyl cyclase of toad urinary bladder.an adenyl cyclase preparation derived from epithelial cells of the urinary bladder of the toad, bufo marinus, is described. this cyclase preparation is specifically stimulated by neurohypophyseal hormones and various synthetic analogs which evoke a hydroosmotic response in the intact bladder. the relative stimulatory effects of these compounds have been compared on the cyclase preparation and in the intact bladder. the peptide concentrations required for half-maximal stimulation (affinity) in th ...19705272332
biochemical studies on the eyes of the toad bufo marinus ictericus. 19705492191
the effects of decapsulation on ion movements across the lens of the toad, bufo marinus. influence on drug actions. 19705530208
uptake and metabolism of catecholamines in the perfused hearts of different species.1. the uptake of (+/-)-(3)h-noradrenaline was studied in isolated perfused hearts of rat, mouse, guinea-pig, pigeon and toad (bufo marinus), and the ic50 (concentration causing 50% inhibition) values for inhibition of uptake of (+/-)-(3)h-noradrenaline by (-)-noradrenaline were calculated. ic50 values ranging from 0.28 mum (rat heart) to 2.34 mum (toad heart) were found.2. in all species except the toad, (-)-noradrenaline showed a higher affinity than (-)-adrenaline for the uptake process, but t ...19705441793
cellular and humoral aspects of the primary immune response of the toad, bufo marinus. 19704190419
comparative immunology: the hemolytic complement system of the anuran amphibian, bufo marinus. 19714396820
tolerance to a protein antigen in a poikilotherm, the marine toad bufo marinus. 19714930986
prolactin, calcitonin, and blood calcium in the toads bufo boreas and bufo marinus. 19715001863
comparative dna renaturation kinetics in amphibians.amphibian haploid genome sizes vary from 9 x 10(8) to 8 x 10(10) nucleotide pairs. the rate of reassociation of dna from amphibians of different genome sizes has been employed to eliminate one of the theoretical models of chromosome structure. scaphiopus couchi, bufo marinus, and rana clamitans, whose haploid genome sizes are in the ratio 2:7:10, all contain sequences of dna represented once in the haploid genome. this indicates that their chromosomes are not composed of identical lateral strand ...19715279521
a comparison of the toxicity of ouabain in vivo and in vitro in the frog, rana pipiens, and the toad, bufo marinus. 19714269642
large-conductance ca2+-activated k+ channels in freshly dissociated smooth muscle cells.freshly dissociated cells from the stomach muscularis of the toad bufo marinus have been employed to carry out a systematic set of electrophysiological studies on the membrane properties of smooth muscle. the existence of ca2+-activated k+ channels became apparent during the first studies under current clamp. in subsequent studies under voltage clamp, a ca2+-activated. tea-sensitive outward current was evident, and it was more than an order of magnitude larger than any other current observed in ...19712427921
increased concentrations of cyclic 3',5'-adenosine monophosphate without a physiological response after antidiuretic hormone.treatment of the serosal surface of the isolated bladders of toads (bufo marinus) with phospholipase c inhibited the hydro-osmotic response to adh, but did not prevent the rise in cyclic amp concentrations associated with hormone action.19714339888
autonomic innervation of the pulmonary vascular bed in a toad (bufo marinus). 19715005760
autonomic innervation of the lung musculature of a toad (bufo marinus). 19715005759
effects of some metabolic inhibitors on the electrical potential difference and short-circuit current across the lens of the toad bufo marinus. 19714999350
temperature dependence of catecholamine depletion by reserpine in the heart of the toad (bufo marinus).1. the catecholamines in toad ventricle were adrenaline (90%) and noradrenaline (10%); there was no dopamine.2. phenoxybenzamine and tyramine stimulated the isolated heart and reduced the catecholamine content.3. reserpine treatment of toads kept at 20 degrees c did not affect the adrenaline but reduced the noradrenaline content of the ventricle.4. at 37 degrees c, reserpine caused depletion of both adrenaline and noradrenaline, and the stimulant actions of phenoxybenzamine and tyramine were los ...19714104653
primary and secondary immune responses of the marine toad (bufo marinus) to bacteriophage f2. 19715551358
myosin-like aggregates in trypsin-treated smooth muscle cells.segments of the lower small intestine of the toad bufo marinus were excised and soaked for approximately 2 hr in ringer's solution (ph 7.4 or 7.8) containing crystalline trypsin and then fixed for electron microscopy at approximately the same ph. thin sections of the tunica muscularis of these specimens show smooth muscle cells ranging in appearance from severely damaged at one extreme to apparently unaffected at the other. among these are cells at intermediate stages, including some which exhib ...19715545103
relationship of na transport and k excretion by the urinary bladder of bufo marinus. 19715540615
contraction of single smooth muscle cells from bufo marinus stomach. 19715002762
muscle spindle response to active muscle shortening in bufo marinus. 19714252497
inhibition of the permeability response to vasopressin and oxytocin in the toad bladder: effects of bradykinin, kallidin, eledoisin, and physalaemin.it has been shown by means of bentley'sin vitro preparation of the isolated urinary bladder of the toad,bufo marinus paracnemis lutz, that bradykinin reversibly inhibited the increase brought about by vasopressin on the permeability to water of the toad bladder. the increased hydro-osmotic response of the bladder to oxytocin was also inhibited by the kinin. the effect on water permeability was observed when bradykinin was added either to the serosal ringer's solution or to the mucosal solution. ...197124174237
the effect of metal ions and antidiuretic hormone on oxygen consumption in toad bladder.1. the sodium-dependent oxygen consumption of pieces of toad bladder (bufo marinus) has been investigated using an oxygen electrode.2. the effect of polyvalent cations (ca(2+), sr(2+), mg(2+), eu(3+), la(3+) and mn(2+)) on sodium-dependent oxygen consumption has been measured. all cations inhibited oxygen consumption, the order of effectiveness being ca(2+) > sr(2+) > mg(2+) > mn(2+) > eu(3+) > la(3+).3. treatment of bladder pieces with antidiuretic hormone (50 m-u./ml.) decreased the effectiven ...19715003482
phylogeny of immunocompetent cells. i. in vitro blastogenesis and mitosis of toad (bufo marinus) splenic lymphocytes in response to phytohemagglutinin and in mixed lymphocyte cultures. 19725023165
[in vitro culture of amphibia anura blood (bufo marinus). study of the behaviour of different types of cells. comparison of these cells with those in the circulating blood]. 19724632846
[hemograft rejection in the toad bufo marinus (author's transl)]. 19724204736
some aspects of the inhibition of the action of antidiuretic hormone by lithium ions in the rat kidney and bladder of the toad bufo marinus.1. the effect of intravenous infusions of various ions on the antidiuretic action of antidiuretic hormone has been studied in rats.2. lithium (13 mmol/l.) reversibly inhibits the antidiuretic responses. similar concentrations of potassium, rubidium, strontium, magnesium, choline and calcium do not. lithium has a similar effect on the antidiuretic activity of oxytocin.3. the inhibition is not simply related to blood nor whole body lithium concentrations.4. lithium (2 mmol/l.) in contact with the ...19724358411
melanophore stimulating hormone: release inhibition by ring structures of neurohypophysial hormones.tocinamide and tocinoic acid, ring structures of oxytocin, are potent inhibitors of the release of melanophore stimulating hormone from the rat and hamster pituitary in vitro. tocinamide is effective at concentrations as low as 10-(14)m on the mammalian pituitary. these peptides do not affect release of the hormone on the frog (rana pipiens) pars intermedia, but they do inhibit release in the bullfrog (rana catesbeiana) and the toad (bufo marinus). the specificity of the peptides on inhibition o ...19724624585
purification and characterization of two classes of immunoglobulins from the marine toad, bufo marinus. 19724625312
spontaneous occurrence and experimental transmission of the fungus, fonsecaea pedrosoi, in the marine toad, bufo marinus. 19734347757
analysis of lactic dehydrogenase in the lethal toad hybrid bufo americanus female times bufo marinus male. 19734197538
the toad's (bufo marinus) lens and urinary bladder as mural membranes: a comparison. 19734197328
effect of phospholipase c on calcium release from epithelia treated with antidiuretic hormone.1. addition of antidiuretic hormone (adh) to the bladders of toads (bufo marinus) preloaded with (45)ca causes an increase in the rate of calcium efflux.2. pretreatment of the serosal surfaces of bladders with phospholipase c prevents the action of adh on calcium efflux.19734353242
cyclic amp and sodium transport. quantitative and temporal relationships in toad urinary bladder.the effects of oxytocin upon tissue camp content and short-circuit current (scc) were measured in the urinary bladder of the toad, bufo marinus. tissue camp levels doubled before any increment in scc was observed, the two hormone responses were quantitatively related, and a threshold level for an effect of camp upon sodium transport was demonstrated. the period of time over which camp levels continued to rise after the threshold level had been attained seemed invariant with hormone concentration ...19734353777
graded contractions in muscle strips and single cells from bufo marinus stomach. 19734197467
the influence of anaesthetics on the increase in the water permeability of the toad bladder induced by vasopressin.1 single lobes of the bladder of bufo marinus were isolated and filled with, and suspended in, oxygenated ringer solution. the fluid in contact with the outside (serosa) of the lobes had a total osmolarity of 225 m-osmol/litre, and that bathing the inside (mucosa) of 45 m-osmol/litre.2 osmotic water flow from mucosa to serosa was measured by weighing the lobes every 30 minutes. it was negligible unless vasopressin was added to the serosal bath. standard concentrations of either 1.25 or 6.25 mu/m ...19744207291
ionic mechanism for the photoreceptor potential of the retina of bufo marinus.1. membrane potentials were recorded from single rods in the isolated retina of bufo marinus while the ionic composition of the extracellular medium was rapidly changed. substitution of 2 mm aspartate(-) for cl(-) produced a prompt depolarization of horizontal cells, but no modification of either resting potential or response to light in receptor cells. this implies that feed-back from horizontal cells to receptor cells was not active.2. during substitution of choline(+) or li(+) for na(+), and ...19744207130
[monolayers of kidney cells from bufo marinus and study of its behaviour in vitro (author's transl)]. 19744219252
aldosterone-induced protein in toad urinary bladder.simultaneous electrophysiological and biochemical experiments demonstrated a specific aldosterone-induced protein in paired urinary hemibladders isolated from the toad bufo marinus. whenever aldosterone stinlmulated short-circuit current, aldosterone specifically increased [(35)s] methionine incorporation into a low-molecular-weight protein (about 12,000). comparative studies with dexamethasone and insulin and inhibitory studies with spironolactone and actinomycin d suggest mineralocorticoid spe ...19744212918
calcium release in relation to permeability changes in toad bladder epithelium following antidiuretic hormone.1. methods for measuring the release of (45)ca from isolated urinary bladders of toads (bufo marinus) pre-loaded with this isotope have been devised. one method allowed separate collection from the mucosal and serosal surfaces of the bladders.2. reducing the ambient calcium concentration reduced the rate of (45)ca efflux suggesting that efflux of radiolabel represents calcium exchange.3. antidiuretic hormone, theophylline and prostaglandin e(1) all increased calcium efflux, while lanthanum and a ...19744374522
the anatomy of the parotoid gland in bufonidae with some histochemical findings. i. bufo marinus. 19744359549
sympathetic cardiac stimulation in bufo marinus under ms-222 anesthesia. 19744359514
translation of rabbit haemoglobin mrna in oocytes of the queensland cane toad, bufo marinus. 19744219274
chromomycosis in the toad (bufo marinus) and a comparison of the etiologic agent with fungi causing human chromomycosis.of 75 toads (bufo marinus) 2 were found infected by black molds. the internal organs of these animals had granulomatous lesions containing brown fungi identical to those found in human chromomycosis. cultures gave rise to slow-growing black molds but all attempts to induce sporulation failed. the fungi did not grow at 36 degrees c or above and failed to hydrolyse gelatin or casein. immunodiffusion and immunoelectrophoresis revealed that both isolates were identical and shared common antigens wit ...1975804722
studies on the interaction of organic phosphates with haemoglobin in an amphibian (bufo marinus), a reptile (trachydosaurus rugosus) and man.the primary organic phosphate modifiers of haemoglobin function are dpg (2,3-diphosphoglycerate) in the toad bufo marinus and atp in the lizard trachydosaurus rugosus. myo-ip6 (myo-inositol hexaphosphate) and myo-ip5 (myo-inositol pentaphosphate) are more effective than atp or dpg in reducing the oxygen affinities of the haemoglobins of b. marinus, t. rugosus and man, while atp and dpg are about equally effective. competition experiments indicate that atp, dpg and myo-ip6 bind to the same site o ...1975811198
a primary immune response of bufo marinus spleen cells in vitro.single-cell suspensions of bufo marinus spleen have been induced to produce a primary immune response to a soluble purified protein. using polymerized flagellin from salmonella adelaide as antigen and culture conditions commonly available in most laboratories but new for amphibian cells, it has been found that in vitro at 37 degree c, toad spleen cells produce an antibody-forming cell response optimal at day 6. the response depends on the number of cultured cells and dose of antigen, and paralle ...1975829903
an autoradiographic evaluation of the regeneration of corneal epithelium in bufo marinus.epithelial regeneration following scraping of a central portion of corneal epithelium of the toad, bufo marinus, was studied. wound closure occurred by migration of a single layer of epithelial cells from adjacent noninjured areas. autoradiography indicated that following wound closure at two days after scraping, dna synthesis began in these epithelial cells covering the former scraped area, and was even more pronounced three days after scraping. at four days the former denuded area was covered ...1975415113
differentiation of antigen-binding cells in the teleost carassius auratus and in the anuran bufo marinus. 1975816712
effects of adapting lights on the time course of the receptor potential of the anuran retinal rod.1. the intracellular receptor potential of the retinal rod cell was recorded in the unperfused, isolated retina of rana catesbiana and in the perfused, isolated retina of bufo marinus. qualitatively, the responses from the two preparations were similar. 2. the rate at which the receptor potential returned to the dark level at the termination of a pulse of light (voff) was measured at a fixed potential chosen to be about 0-6 of the way from the dark level to the peak of the response. 3. when the ...1975805837
surface modifications evoked by antidiuretic hormone in isolated epithelial cells: evidence from lectin probes.epithelial cells (80-90% "granular" type) were isolated from urinary bladders of bufo marinus and rana catesbiana. the inhibitory effect of alpha-methyl-d-mannoside on fluorescein-labeled concanavalin a (con a) binding to these cells indicates that they possess specific binding sites for con a. the lectin also mediates adsorption of erythrocytes to these cells. both con a binding and con a-mediated hemadsorption to epithelial cells are depressed at 4 degrees c, as compared with cells maintained ...1975813065
contraction of isolated smooth muscle cells by inophore a23187.ionophore a23187 causes contraction of smooth muscle cells isolated from the stomach muscularis of bufo marinus. the peak response is reached within 10 sec of inophore addition and then decays to a lesser, sustained contraction. the initial phase of contraction is maximal at a23187 concentrations greater than 5 x 10(-6) m and half maximal at 5 x 10(-7) m. chelation of extracellular calcium by ethyleneglycol-bis(beta-aminoethylether)-n,n'-tetraacetic acid (egta) does not affect the initial contra ...1975812094
axoplasmic transport in the toad bufo marinus.the rate and course of axoplasmic transport from the eighth dorsal root ganglion cell bodies into the sciatic nerve of the toad bufo marinus were studied. concentrated tritiated proline was hydraulically injected into a surgically exposed dorsal root ganglion of animals maintained at 19 +/- 0.5 degrees c. at postinjection intervals of 1, 6, and 10 h, the animals were sacrificed and the dorsal root, ganglion, and sciatic nerve were removed bilaterally. the dorsal roots and peripheral nerves were ...197551674
influence of environmental salinity on renal and adrenocortical function in the toad, bufo marinus. 1975812762
effect of haemin on endogenous protein synthesis in oocytes of the queensland cane toad bufo marinus.although general protein synthesis as measured by l-[3h]leucine incorporation is unaffected by injection of haemin into oocytes of b. marinus, the synthesis of at least two proteins is repressed. it appears that haemin is capable of exerting inhibitory effects on eukaryote protein synthesis as well as stimulating it as previously reported by other workers.1975810125
inhibition of active sodium transport by radiographic contrast media.we demonstrate that salts of diatrizoate and iothalamate, radiographic contrast agents, depress the active transport of sodium in the urinary bladder of the columbian toad, bufo marinus. isolated toad bladders were incubated in isotonic ringer's solutions with isosmolar displacement of sodium chloride by contrast media in experimental solutions. sodium transport as measured both by short-circuit current (scc) and by isotopic sodium flux was significantly depressed in the presence of sodium diatr ...1975803600
effect of steroid depletion on the response of toad bladder to vasopressin.1. we have investigated the water transport and short-circuit current (s.c.c.) response to vasopressin (1 mu./ml. and 100 mu./ml.) in isolated toad urinary bladders (bufo marinus) following overnight incubation in the presence or absence of steroid-containing ringer solution. 2. the water transport response to the lower dose of vasopressin (1 mu./ml.) was considerably reduced in 'steroid depleted' conditions, wheras the response to the higher dose of vasopressin (100 mu./ml.) was not similarly a ...1975810580
ascorbic acid stimulates chloride transport in the amphibian cornea.the cornea of the toad, bufo marinus, actively transports chloride from the endothelial to the epithelial surface. this transport process has been related to the maintenance of the normal transparency of the cornea. ion transport, as evidenced by the short-circuit current (scc), is markedly stimulated by physiologic concentrations of ascorbic acid. measurement of the unidirectional fluxes of 36cl and 22na shows that the increase in scc is due primarily to a stimulation of the active transport of ...1975810451
excretion of hco3- by the urinary bladder of bufo marinus in metabolic alkalosis.we studied the role of the urinary bladder of bufo marinus in the excretion of bicarbonate into the urine. the toads were in metabolic alkalosis, produced by administering 120 mm nahco3 by stomach tube or by soaking the toads in 120 mm nahco3 solution for 48 to 72 hr. in vitro 10 cannulated whole bladders from toads in alkalosis transported bicarbonate from the serosal to mucosal medium. the average gradient created by this transport was 5.7 meq/1. in 15 whole bladders from toads in metabolic ac ...1975810907
coupling of sodium transport to respiration in the toad bladder.energy expenditure and transepithelial sodium transport were measured continuously and simultaneously from isolated urinary bladders of the dominican toad, bufo marinus. sodium transport was measured as the short-circuit current and co2 produced by the bladder was measured conductometrically by the method of maffly. the rates of sodium transport and co2 productions were linearly related. the slope of the regression of sodium transport on co2 production, djna/djco2, was found to be quite similar ...1975805249
negative potential level in the outer layer of the toad skin.the isolated skin of the toad bufo marinus ictericus when impaled from the outer surface by glass microelectrodes filled with 3 m kcl shows a voltage profile which is a continuous function of the depth of impalement. the superficial intraepithelial potential difference measured with reference to the external solution (pdi) is negative with nacl-ringer's solution on both sides of the skin, displaying a minimum of -26.7+/-3.6 mv at 6+/-2 mum. null value is obtained at 19+/-3 mum, with positive val ...1975507
oscillations in rod and horizontal cell membrane potential: evidence for feed-back to rods in the vertebrate retina.1. rods and horizontal cells were studied with intracellular recordings in the retina of the toad, bufo marinus; 161 cells were from the eyecup preparation and thirty were from the isolated perfused retina. 2. of these cells, 39% exhibited either transient or sustained oscillations of membrane potential. light flashes either evoked transient oscillations or temporarily abolished sustained oscillations. the amplitudes of the oscillations could be as large as 27 mv. the frequency of the oscillatio ...1976825636
sodium transport by the colon of bufo marinus: na uptake across the mucosal border.na transport by the isolated toad colon has been studied by measuring transmural na fluxes and by direct measurement of the na influx across the mucosal border. net na transport accounts for 88% of the short circuit current in the presence and in the absence of exogenous aldosterone. na influx across the mucosal border appears to consist of two components. one component is highly correlated with short circuit current, is a saturable function of mucosal na concentration, and is inhibited by lithi ...1976823339
estimation of the lifespan of amiloride binding sites in the membranes of toad bladder epithelial cells.1. sodium entry sites in the membranes of isolated epithelial cells prepared from bladders of toads (bufo marinus) have been labelled with amiloride. the number of binding sites remained constant in suspensions for up to 100 hr. 2. in the presence of a protein synthesis inhibitor (cycloheximide, 0-5 mug/ml.) there was a decline in the density of binding sites was approximately exponential. regression analysis gave a half-life of approximately 60 hr. 3. aldosterone (5 x 10(-8) m) caused a signifi ...1976817015
the anatomy of the pulmonary vascular bed in the toad bufo marinus.1. the pulmonary vascular anatomy of the toad, bufo marinus was studied by scanning electron microscopy of vascular corrosion casts and of tissues prepared for light microscopy. 2. the lung is divided by septa into three orders of alveoli. arterial branches run in the septa and cannot be observed directly through the lung surface. 3. the capillary bed forms a meshwork over the lumenal surface of septa and lung walls. it is divided into longitudinal zones of arterial distribution; it is broken al ...1976813828
actions of aldosterone on polyadenylated ribonucleic acid and na+ transport in the toad bladder.polyadenylated ribonucleic acid [poly(a)(+)-rna] has been isolated from the cytoplasm of the epithelium of the urinary bladder of the toad (bufo marinus) by oligo-(deoxythymidylate)cellulose chromatography. aldosterone increased the incorporation of [3h]uridine, and of [3h]uridine and [3h]adenosine (given in combination) into 7s, 12s, and 18s poly(a)(+)-rna during the first 30 min of the action of the hormone, as defined by either a pulse or pulse-chase sequence. the quantity of cytoplasmic poly ...1976822868
sensitivity of toad rods: dependence on wave-length and background illumination.1. there are five morphological types of photoreceptors in the retina of the toad, bufo marinus: red and green rods, single cones, and the principal and accessory members of double cones. the largest and most abundant of these is the red rod. 2. intracellular recordings were used to investigate the dependence of the sensitivity of red rod responses on wave-length and background light. 3. the spectral sensitivity of dark-adapted and moderately light-adapted red rods can be satisfactorily fitted w ...1976825637
effects of parathyroid hormone on h+ and nh+4 excretion in toad urinary bladder.the urinary bladder of bufo marinus excretes h+ and nh+4, and the h+ excretion is increased after the animal is placed in metabolic acidosis. the present study was done to determine if parathyroid hormone could stimulate the bladder to increase the excretion of h+ and/or nh+4. parathyroid hormone added to the serosal solution in a final concentration of 10 mug/ml was found to increase h+ excretion by 50 per cent above the control hemibladders, while there was no effect on nh+4 excretion. parathy ...197613223
the innervation of the cutaneous artery in the toad bufo marinus. 1976828117
effects of aldosterone on na+ transport in the toad bladder. ii. the anaerobic response.the action of aldosterone on active na+ transport was assessed under aerobic and anaerobic conditions in the isolated urinary bladder of the toad, bufo marinus. aldosterone augmented the short-circuit current (isc) under rigorous anaerobiosis. four lines of evidence indicate that the increase in anaerobic isc does not represent an equivalent increase in active na+ transport: 1. net na transport, determined by isotopic fluxes, was the same in the aldosterone-treated and control quarter-bladders, ...1976825139
motor innervation of the toad iris (bufo marinus).the sphincter pupillae muscle cells in the iris of bufo marinus contract autonomously in response to bright light, causing a rapid constriction of the pupil. a strong sympathetic beta-adrenergic inhibition of the sphincter pupillae is apparent in this species. the inhibitory fibers can originate in the second, third, or fourth ventral spinal roots. no strong, consistent excitatory innervation of the toad iris was detected, even by transmural stimulation of the isolated iris. pupilloconstriction ...1976824959
effects of the group iub metals (cd, zn and hg) on the permeability of the crystalline lens of the toad (bufo marinus). 1976824178
the passive permeability of the skin of anuran amphibia: a comparison of frogs (rana pipiens) and toads (bufo marinus).1. efflux of na across dorsal skin, in vitro (bathed on both sides with ringer solution), of frogs and toads were similar, but it was greater in ventral skin from the latter. 2. the efflux of na declined, in both species, when the external surface of ventral, but not dorsal, skin was exposed to hyposmotic solutions with a low na concentration. this change in na permeability was influenced by the low osmotic concentration as well as the low na concentration. 3. efflux of cl was similar in both th ...1976824445
comparative ultrastructural analysis of two tortoise bladders, testudo graeca and geochelone carbonaria.urinary bladders from the desert tortoises, testudo graeca and geochelone carbonaria were removed at specific times during the year and species in all bladders examined: (1) granular cells, (2) mitochondria-rich cells, and (3) basal cells. cells analogous to these three types have also been observed in amphibian bladders (from toad bufo marinus and bullfrog, rana catesbiana) and reptilian bladders (from pseudemys scripta and clemmys caspica). both tortoises have an incomplete layer of basal cell ...19761252017
cyclicity and memory in the humoral immune response of the marine toad bufo marinus.bufo marinus toads immunized with a single dose of 100 mug of polymerized flagellin (pol) produce a longlasting cyclic humoral response at 22 degrees c in which the serum antibody titers rise and fall within periods of 2-3 weeks. this seems to be regulated by the catabolism of immunoglobulins, since passive 125i-labeled igm in the serum has a half-life of 17 days, corresponding to the cyclicity of the titers of active antibodies. in toads injected with between 10 ng and 10 mug antigen the serum ...1976825371
tazonomy of toxoplasma.after reviewing reports of the hosts, structure and life cycle of toxoplasma, the genus is placed in the apicomplexan family eimeriidae and the folllowing 7 species are recognized: toxoplasma gondii (nicolle & manceaux) (type species) from about 200 species of mammals and birds, with oocysts in felids; toxoplasma alencari (da costa & pereira) from the frog leptodactylus ocellatus; toxoplasma brumpti coutelen from the iguana iguana tuberculata; toxoplasma colubri tibaldi from the snakes coluber m ...1977325203
differences in pulmonary microvascular anatomy between bufo marinus and xenopus laevis.1. histological and corrosion-casting techniques have been used to provide a comparison of lung structure between a terrestrial load (bufo marinus) and an aquatic one (xenopus laevis). the pulmonary microvascular anatomy is distinctly different in these two species and both differ from classical descriptions of other anuran lungs. 2. in x. laevis large peribronchial vessels form a number of direct connections between the pulmonary artery and vein at the base of the lung. as a result of their loc ...1977402217
electrical responses of rods in the retina of bufo marinus.1. intracellular responses to flashes and steps of light have been recorded from the outer segment and the cell body of rods in the retina of the bufo marinus. the identification of the origin of recorded responses has been confirmed by intracellular marking.2. responses to flashes delivered in darkness or superimposed on a background were analysed. responses recorded from outer segments conform to the principle of ;spectral univariance'. the shape of the response is not affected by enlarging th ...1977406383
endogenous digitalis-like activity in the plasma of the toad bufo marinus. 1977221828
reorientation of myofilaments during contraction of a vertebrate smooth muscle.the purpose of the investigation was to determine whether filaments within smooth muscle cells changed their orientation (with respect to the main axis of the cell) during contraction. the stomach muscle of bufo marinus was used, since its cells may be easily isolated, enabling direct observation in living cells. in addition to still micrography, cinemicrography was used to record continuously during contraction. polarization microscopy revealed a change in birefringence after contraction, with ...1977402082
effects of carbamazepine on the water permeability and short-circuit current of the urinary bladder of the toad and the response to vasopressin, adenosine 3',5'-cyclic phosphate and theophylline.carbamazepine has been reported to decrease urine output and increase urinary concentration in patients with diabetes insipidus. the effects of the drug on the osmotic water permeability of the bladder of the toad, bufo marinus, were studied. carbamazepine had no effect on osmotic water flow when present in the serosal or mucosal bathing media. the submaximal or maximal increase in osmotic water flow caused by vasopressin was inhibited by serosal carbamazepine concentrations as low as 0.01 mm. h ...1977189008
electrical and adaptive properties of rod photoreceptors in bufo marinus. i. effects of altered extracellular ca2+ levels.the effects of altering extracellular ca(2+) levels on the electrical and adaptive properties of toad rods have been examined. the retina was continually superfused in control (1.6 mm ca(2+)) or test ringer's solutions, and rod electrical activity was recorded intracellularly. low-calcium ringer's (10(-9)m ca(2+)) superfused for up to 6 min caused a substantial depolarization of the resting membrane potential, an increase in light-evoked response amplitudes, and a change in the waveform of the l ...1977412914
electrical and adaptive properties of rod photoreceptors in bufo marinus. ii. effects of cyclic nucleotides and prostaglandins.substances known to alter cyclic nucleotide levels in cells were applied to the isolated toad retina and effects on rod electrical and adaptive behavior were studied. the retina was continually superfused in control ringer's or ringer's containing one or a combination of drugs, and rod activity was recorded intracellularly. superfusion with cgmp, bu(2)gmp, isobutylmethylxanthine (ibmx; a phosphodiesterase inhibitor), or pgf(2alpha) (a prostaglandin) caused effects in rods that closely match thos ...1977201724
effect of hypothalamic lesions on water metabolism of the toad bufo marinus.the rate of cutaneous water uptake after dehydration was significantly depressed in functionally neurohypophysectomized toads (bufo marinus), which consequently regained weight much more slowly than intact toads when returned to water. toads bearing hypothalamic lesions were able to develop an antidiuresis when removed from water to a saturated atmosphere, but the antidiuresis was solely glmerular in origin and was established more slowly than in intact animals. the fractional reabsorption of fi ...1977411867
contribution of mucosal chloride to chloride in toad bladder epithelial cells.epithelial cells were scraped from the bladders of toads of the species bufo marinus obtained from the dominican republic. these epithelial cells exchanged their chloride virtually completely with 36cl i; the medium within 60 min. of this chloride, about 93% came from the serosal medium. the approximately 20 mmole/kg dry wt of chloride which equilibrates with 36cl in the mucosal medium was still present when choline replaced sodium in the medium in the presence of amiloride (10(-4) m) and was al ...1977408496
effects of injections of calcium and egta into the outer segments of retinal rods of bufo marinus.1. intracellular recordings were made from the outer segments of rods in the isolated, superfused retina of bufo marinus. cells were impaled under observation with a compound microscope fitted with an infra-red image converter. changes of membrane voltage and some concomitant changes of input resistance were measured in response to light, membrane polarization and iontophoretic injections.2. by means of a double barrel micropipette, charge was passed into a rod from a micropipette barrel that co ...1977408483
the effect of progressive hypoxia on respiration in the toad bufo marinus.1. as bufo marinus became progressively hypoxic over a period of 90 min, there was a rise in arterial ph, presumably brought about by hyperventilation. the alkalosis gradually disappeared when oxygen levels became very low. it is suggested that this is the result of a respiratory or a metabolic ph adjustment, or both. 2. hypoxic animals developed a characteristic breathing pattern in which discrete periods of lung ventilations alternated with buccal oscillations or respiratory pauses. 3. a prono ...197719550
effects of 3'-deoxycytidine on rrna synthesis in toad bladder: analysis of response to aldosterone.previous studies showed that aldosterone augments transepithelial active na+ transport and the incorporation of [3h]uridine into polyadenylated rna (poly(a)(+)-rna) (putatively mrna) early in the latent period. soon thereafter, incorporation of [methyl-14c] groups, as well as [3h]uridine into rrna is also increased. to evaluate the role of rrna in mineralocorticoid action, the inhibitor 3'-deoxycytidine was used in studies on the urinary bladder of the toad bufo marinus. 3'-deoxycytidine suppres ...1977404886
movement of the hyoid in frogs during feeding.feeding, breathing, and vocalization sequences of bufo marinus were recorded by cineradiography. results of film analysis indicate that the hyoid moves during all three behaviors. movement of the hyoid is critical in tongue protrusion of frogs, and a biomechanical model of this action is presented. the hyoid appears to represent a compromise morphological system for three functions, rather than an optimal system for any one. this may explain, in part, the retention of a relatively inefficient br ...1977404864
characteristics of response of isolated smooth muscle cells to cholinergic drugs.the contractile responses of suspensions of isolated smooth muscle cells from the stomach muscularis of bufo marinus were assessed with a coulter counter. contractile responses of strips from the same tissue were recorded isotonically. suspensions of isolated smooth muscle cells exhibit a dose-dependent graded response to cholinergic agonists. the intact tissue has a lower sensitivity than the isolated cells to acetycholine but a higher sensitivity to carbachol. the higher sensitivity of isolate ...1977402821
detection of contraction of isolated smooth muscle cells in suspension.a coulter counter has been utilized to assess the contractile state of suspensions of isolated smooth muscle cells prepared by enzymatic digestion of stomach muscularis of bufo marinus. pulse-duration and pulse-hieght histograms were constructed from the pulses that occur as cells pass through the coulter counter orifice. contraction of cells in suspension causes shifts in these pulse histograms to a greater percent of shorter duration pulses and of larger pulse heights. these shifts are consist ...1977402820
active phosphate transport across the urinary bladder of the toad, bufo marinus.net transport of inorganic phosphate occurs in the absence of an electrochemical gradient from the mucosal to the serosal bathing solution in the isolated toad urinary bladder. this transport can be inhibited by metabolic inhibitors. the magnitude of this transport can be altered by changes in phosphate concentration or by the addition of parathyroid hormone.1977405496
binding of aldosterone to cytoplasmic and nuclear receptors of the urinary bladder epithelium of bufo marinus.binding of aldosterone to cytoplasmic and nuclear sites in urinary bladder epithelia of bufo marinus (dominican variant) is saturable and dependent upon steroid concentration. scatchard analysis of specific cytoplasmic binding yielded a maximal binding capacity (n) of 14.5 x 10(-14) mol/mg protein and an apparent equilibrium dissociation constant (kd) of 1.4 x 10(-8) m. since scatchard analysis of specific nuclear binding was complex, this binding was resolved by a computer-generated cirve-fitti ...1978211852
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