Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01178 (oxytocin)
 15,767 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Arginine vasotocin (AVT) and oxytocin (OXY), in the dose range of 2 X 10(-13)-2 X 10(-8) mol, were found to be potent vasoconstrictors of the arterioarterial pathway of isolated perfused eel gills. AVT was significantly (P less than 0.05) more potent than OXY, as indicated by the results of both dose- and concentration-response curves. Isotocin (IT) and arginine vasopressin (AVP) were unable to elicit a vascular response at doses of up to 2 X 10(-8) mol. The arteriovenous component of branchial flow was not affected by these four peptides. Results from constant-pressure head and constant-flow preparations yielded similar results.
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PMID:The effects of neurohypophysial hormones on the vascular resistance of the isolated perfused gill of the European eel, Anguilla anguilla L. 355 80

Neurohypophysial hormone precursors are small proteins processed into several fragments during axonal transport from hypothalamus to neurohypophysis. From 3-month-old fetal bovine pituitaries the three fragments of vasopressin precursor, arginine vasopressin, MSEL-neurophysin and copeptin, and the two fragments of oxytocin precursor, oxytocin and VLDV-neurophysin, have been isolated and characterized. These polypeptides are identical to those previously identified in the late fetus (7-9 months old) and in the adult. It is concluded that the same genes are expressed during fetal and adult lives, the vasopressin gene appearing roughly four times more active than the oxytocin gene in the early fetus. Vasotocin, mesotocin and additional neurophysin have not been detected in the early fetus.
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PMID:Ontogeny of the bovine neurohypophysial hormone precursors. III. Identification of neurohormones, neurophysins and copeptin in the early bovine fetus. 361 Apr 75

Serum from a patient who had been treated with Pitressin for extended periods was evaluated for the presence of autoantibodies. When this immune serum was used with either an immunofluorescence or an heterologous immunoperoxidase technique, positive staining was observed in the neurophysin-containing cells of the rat supraoptic, paraventricular and suprachiasmatic nucleus. Whereas the immune serum may also be expected to contain antibodies against oxytocin, vasopressin and the anterior pituitary hormones, this could not be substantiated with the immunohistochemical procedures.
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PMID:Use of a cross-species immunohistochemical procedure to demonstrate the presence of neurophysin antibodies in the serum of a patient treated with Pitressin. 371 17

Unilateral microstimulation of the medial parvocellular division of the hypothalamic paraventricular nucleus (PVNmp) elicits significant increases in gastric acid secretion and bradycardia. An injection of 25 picomoles of the oxytocin antagonist dET2Tyr(Et)Orn8 Vasotocin (ETOV), suspended in 5 nanoliters of artificial of cerebrospinal fluid (CSF), into the dorsal motor nucleus of the vagus (DMN) immediately preceding microstimulation of the PVNmp suppresses this change in gastric acid secretion and heart rate. The injection of an equal volume (5 nanoliters) of artificial CSF vehicle solution into this region of the DMN, prior to PVNmp microstimulation, has no effect on either the subsequent stimulation-evoked changes in acid secretion or cardiac activity. This suppression of PVNmp stimulation-evoked changes in gastric acid levels and heart rate by the presence of the oxytocin antagonist, ETOV, within the DMN supports the hypothesis that oxytocin may be a neurotransmitter used for descending communication from the PVNmp to neurons within the DMN that regulates these two functions.
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PMID:Hypothalamic paraventricular nucleus stimulation-induced gastric acid secretion and bradycardia suppressed by oxytocin antagonist. 376 42

Arginine vasotocin ([8-arginine]-oxytocin) (AVT), the primary antidiuretic principle in submammalian vertebrates, has been reported to be present in mammalian pituitary and pineal glands. Although the most phyletically ubiquitous of the known neurohypophysial peptides, AVT is still not recognized as a mammalian hormone. We examined plasma, urine, and amniotic fluid from fetal lambs by radioimmunoassay (RIA) for evidence of AVT to assess the possibility of its being such a hormone. Measureable quantities of AVT-like immunoreactivity (irAVT) were observed in fetal plasma (2.4 +/- 0.2 pg/ml), urine (1.4 +/- 0.2 pg/ml), and amniotic fluid (1.9 +/- 0.2 pg/ml). Since the AVT antiserum shows minimal cross-reactivity with arginine vasopressin (AVP) and oxytocin (OT), measurements of AVP and OT concentrations in the same biological fluids also were conducted with specific antisera. The results suggest that the irAVT was not accountable on the basis of cross-reaction. To further verify the identity of the irAVT, a high pressure liquid chromatography system using RIA as a means of detection was developed. This system is sufficiently sensitive to allow the separation and quantitation of picogram quantities of the synthetic peptides AVT, AVP, and OT. In this system, the irAVT in fetal plasma, urine, and amniotic fluid appeared as a single peak coeluting with synthetic AVT. These results indicate that AVT is present in ovine fetal plasma and support the view that the fetus secretes this peptide. The physiological significance of circulating AVT remains to be defined.
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PMID:Arginine vasotocin in ovine fetal blood, urine, and amniotic fluid. 399 51

1. When Rana cancrivora collected from fresh water had been exposed for 3 days to saline solutions having osmolalities from 280 to 690 m-osmole/kg, urea concentrations in plasma and urine appeared to come into equilibrium, and were from 70 to 200 m-mole/l.2. Plasma urea level of fresh water R. cancrivora (48 m-mole/l.) was doubled (82 m-mole/l.) after 8 hr of exposure to 270 m-osmolal saline. It continued the same after 24 hr of exposure.3. When isolated urinary bladders of R. cancrivora were exposed to Ringer on the serosal aspect and one-fifth Ringer on the mucosal aspect, then in response to this osmotic difference of 190 m-osmole/kg, the rate of fluid movement (mucosa to serosa), which was 10.3(+/-2) mul./cm(2).hr, was not significantly altered when up to 60% of the NaCl of the Ringer solution was substituted by urea.4. Under the same circumstances, when oxytocin (50 m-u./ml.) was present in the serosal solution, the rate of fluid movement (mucosa to serosa) was 133.2(+/-7.9) mul./cm(2).hr in the absence of urea; it was progressively decreased by the presence of urea until, when 80% of the NaCl had been substituted by urea, the rate of fluid movement was reduced to 14.5(+/-4.0) mul./cm(2).hr.5. The diminished rate of fluid movement under the above circumstances could not be correlated with serosal urea concentration, with serosal availability of Na(+), nor with Na(+) concentration difference across the bladder wall. It appeared to be directly related to the ;non-urea osmotic difference' across the bladder wall provided by solutes other than urea.6. When isolated bladders were exposed to an osmotic difference of 190 m-osmole/kg, but having 25 mM urea present in the mucosal solution, then fluid moved from mucosa to serosa at a rate of 10.4(+/-1.3) mul./cm(2).hr in the absence of oxytocin and 124(+/-9) mul./cm(2).hr when oxytocin (50 m-u./ml.) was present. In the former case no urea passed across the bladder wall, but in the latter case urea passed from mucosa to serosa at a rate of 3.16(+/-0.3) mumole/cm(2).hr. The fluid moving from mucosa to serosa thus contained urea 25.5 m-mole/l.7. Vasotocin (10(-9)M), which is equipotent with oxytocin (50 m-u./ml.) in affecting permeability of the isolated urinary bladder to water, was also equipotent in producing a reduced rate of water fluid movement in the presence of 40% urea (vasotocin, 63 mul./cm(2).hr; oxytocin, 59 mul./cm(2).hr).8. When groups of frogs were cystectomized, and other groups of frogs were sham-operated, then after 48 hr of exposure to fresh water or to 300 m-osmolal saline the sham-operated frogs had plasma urea level raised from 20 m-mole/l. (fresh water) to 42 m-mole/l. (saline), while the cystectomized frogs had 20 m-mole/l. (fresh water) and 26 m-mole/l. (saline).9. The hypothesis is presented that hormone-induced permeability of the urinary bladder to urea contributes to the immediate adjustment of plasma urea level by which R. cancrivora survives when exposed to high environmental salinity.
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PMID:Permeability of urinary bladder of Rana cancrivora to urea in the presence of oxytocin. 504 40

Five amphibian species were studied for the effect of hypophysial hormones on their water balance. The species were three anurans, Rana ridibunda, Bufo viridis and Pelobates syriacus, and two urodeles Salamandra salamandra and Triturus vittatus. In the first four species different stages of development were studied, in the newt both the terrestrial and aquatic phases of the adult were examined. The hormones used were oxytocin (OXY), arginine vasotocin (AVT) and prolactin (PL). Oxytocin caused most water retention when compared with the other hormones, especially responding were juveniles of Rana and Bufo, but also the terrestrial phase of the adult newt Triturus. Arginine vasotocin affected mostly juvenile Pelobates. Prolactin caused water retention in juvenile Rana and in the terrestrial phase of Triturus. In general the hormones affected the juvenile stages more than either larvae or adults.
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PMID:Water balance of five amphibian species at different stages and phases, as affected by hypophysial hormones. 613 81

The regulation of sperm transport through the Wolffian duct of male amphibians is poorly understood. These experiments were conducted using rough-skinned newts (Taricha granulosa) to determine if Wolffian ducts are capable of contracting in vitro and, if so, to characterize the contractile responses to acetylcholine (ACh), norepinephrine (NE), and neurohypophysial hormones. Dose-response curves for NE and ACh, which were prepared by measuring isometric contractions, are similar to those reported for mammalian vas deferens. For NE, the minimum effective dose and ED50 were found to be 1 X 10(-5)M and 4.17 X 10(-5)M, respectively. For ACh, the minimum effective dose was 3.2 X 10(-8)M and the ED50 was 1.37 X 10(-5)M. Alpha-adrenoreceptors appear to mediate the contractile responses to NE because phentolamine (10(-5)M) blocked or attenuated the response to NE (10(-6)M, 10(-5)M or 10(-4) M). Beta-adrenoreceptors appear to mediate relaxation because dichloroisoproterenol (10(-5)M) enhanced the response to 10(-5)M NE. The contractile response to three neurohypophysial hormones were also investigated. Arginine vasotocin was more effective in eliciting contractions than oxytocin. The effect of lysine vasopressin was intermediate between arginine vasotocin and oxytocin. These experiments demonstrate that amphibian (Taricha) Wolffian ducts contract in vitro in response to neurotransmitters and neurohypophysial hormones. The contractile response to neurotransmitters occurs in a dose-dependent manner; the response to neurohypophysial hormones is hormone specific.
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PMID:Contractions of amphibian Wolffian duct in response to acetylcholine, norepinephrine, and arginine vasotocin. 630 30

Arginine vasotocin (AVT) has been measured in neonatal cerebrospinal fluid (CSF) and human amniotic fluid using a newly developed specific radioimmunoassay system. There were significant amounts of AVT in all samples. Vasopressin and oxytocin also were measured in the samples and could not account for the levels of vasotocin found. The source and function of these neurohypophyseal peptides in CSF and amniotic fluid remains speculative.
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PMID:Radioimmunoassay of vasotocin, vasopressin, and oxytocin in human neonatal cerebrospinal and amniotic fluid. 669 69

The distribution of vasotocin and isotocin in the brain of the rainbow trout Salmo gairdneri was investigated by the unlabeled antibody enzyme method, by using purified antisera against arginine vasotocin and isotocin. In the preoptic nucleus no clear differences were observed in the distribution of vasotocin- and isotocin-containing cells. Vasotocin and isotocin innervation was found in most brain regions, though in general isotocin fibers were much more abundant. The area dorsalis pars medialis of the telencephalon, the saccus dorsalis, and the basal part of the nucleus recessus posterioris were found to be innervated by vasotocin and scarcely by isotocin fibers. In the nucleus habenularis, the nucleus recessus lobus lateralis, the nucleus preglomerulosus pars medialis, and the tectum mesencephali isotocin fibers prevailed. These findings in the trout brain are compared with the vasopressin and oxytocin innervation of the rat brain.
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PMID:The distribution of vasotocin and isotocin in the brain of the rainbow trout. 676 94


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