Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01185 (vasopressin)
 23,126 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the present paper the effects of nonapeptide hormones and of some of their chemical analogues were investigated on progesterone and testosterone production in granulosa cells of sow ovaries; the experiments were made in vitro. This objective was given by data on potential regulatory roles of nonapeptides at the level of hypothalamus, pituitary and reproductive organs. The goal of this experiment was to analyze the effects of various doses of oxytocin (OT), arginine-8-vasopressin (AVP), arginine-8-vasotocin and of some of their analogues on progesterone and testosterone production in vitro in granulosa cells of sow ovaries. The production activity of granulosa cells was investigated which were obtained from slaughtered sows without any changes in their reproductive process and abnormalities in their reproductive organs. Follicles of the size 2-5 mm without marked paleness in the early follicular phase were selected for aspiration. Granulosa cells with determined viability (more than 75%) and concentration (2 million/ml) were cultivated in defined culture conditions (37.5 degrees C, 5% CO2) after threefold resuspension and centrifugation of follicle fluid. These hormonal preparations were used in the experiments: pFSH, synthetic OT, synthetic AVP, synthetic AVP with antidiuretic effects and synthetic AVT. Progesterone and testosterone concentrations were analyzed radioimmunoanalytically using commercial kits of the Institute of Radio ecology and Nuclear Technology at Kosice. Statistically significant differences between the groups were evaluated by Student's t-test. The administered preparations were found to influence progesterone and testosterone production in dependence on the doses applied (Figs. 1-6). OT stimulation of progesterone production in granulosa cells indicated its regulatory role in relation to secretion of this hormone.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Production of progesterone and testosterone in ovarian granulosa cells in sows after administration of nonapeptide hormones in vitro]. 141 99

In anaesthetized rats, ventilatory stimulation induced by phentolamine, an alpha sympatholytic agent, emphasizes the role of some adrenergic mechanisms in the control of the respiratory centres activity. Phentolamine (5 and 10 mg.kg-1, iv) stimulates ventilation after a 4 s latency, tidal volume and respiratory rate being both increased. A same response can also be provoked 10 min later, by a second identical iv administration, systemic blood pressure remaining then stable at its previous low level. Hyperventilation is also observed when phentolamine is injected in totally denervated rats, without any remaining baro- or chemosensitivity. Stimulation is thus due to a central activity in relation with the release of inhibitory influences. Phentolamine also causes hyperventilation after prazosin pretreatment indicating that the alpha 1 adrenergic blockade is not involved in the post-phentolamine stimulation. This is an alpha 2 adrenergic transmission dependent mechanism. Variation of the systemic blood pressure is not the main mechanism involved in the hyperventilation induced by phentolamine. Meanwhile, baroreceptor activity modulates the central response to the drug, as shown by the negative influence of the post-vasopressin arterial hypertension. Hyperoxia is also a modulating factor acting by two ways: an inhibition of the peripheral chemoreceptors activity is added to an arterial hypertension. On the other side, activation of these chemoreceptors by almitrine bismesilate increases the respiratory responses to phentolamine. As already shown by one of us (Lagneuax, 1986), phentolamine pretreated rats are more responsive to hypoxia and to almitrine. Moreover, these phentolamine pretreated rats are protected against cardiovascular collapses and against apnea, frequently observed during hypoxia without CO2 compensation.
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PMID:[Alpha 2 adrenergic control of ventilation in the rat]. 170 84

Experiments were designed to determine the endothelium-dependent and endothelium-independent responses to aggregating platelets in porcine pulmonary arteries. Isolated rings with and without endothelium from large (5-7-mm-diameter) and small (2-3-mm-diameter) pulmonary arteries were suspended in modified Krebs-Ringer bicarbonate solution bubbled with 95% O2-5% CO2 in the presence of indomethacin. Aggregating platelets caused relaxations in rings with endothelium but contractions in rings without endothelium, both of which were significantly larger in small versus large pulmonary artery rings. Serotonin and ADP caused concentration-dependent endothelium-augmented relaxations that were unaffected by ketanserin. Methiothepin, but not apyrase, significantly decreased the platelet-induced endothelium-dependent relaxations; the residual relaxation was abolished when rings were incubated with methiothepin, apyrase, and theophylline but was unaffected if apyrase was absent, indicating that ADP is responsible for the residual relaxation caused by aggregating platelets. Quiescent rings, with and without endothelium, contracted in a dose-dependent manner to norepinephrine and histamine but not to serotonin or vasopressin. The contraction to aggregating platelets was blocked by methiothepin, pyrilamine, and diphenhydramine but was unaffected by phentolamine, ketanserin, or incubation of the platelets with dazoxiben. These data indicate that, in large and small porcine pulmonary arteries, serotonin and ADP are the major contributors to the endothelium-dependent relaxation caused by aggregating platelets, while histamine appears to be responsible for the contraction that platelets cause in rings without endothelium.
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PMID:Heterogeneity of endothelium-dependent and endothelium-independent responses to aggregating platelets in porcine pulmonary arteries. 201 1

To determine mechanisms of intracellular pH (pHi) regulation in mouse medullary thick limbs (MTAL), pHi was measured in MTAL suspensions and in the isolated perfused MTAL by use of 2',7'-bis(carboxyethyl)-5(6)carboxyfluorescein (BCECF). A method to obtain MTAL suspensions from the mouse outer medulla is reported. Characterization of suspensions with microscopy, anti-Tamm-Horsfall antibody labeling, measurement of O2 consumption, and adenosine 3',5'-cyclic monophosphate responses to antidiuretic hormone indicated that these suspensions were highly purified for viable MTAL tubules. The resting pHi was 7.41 +/- 0.02 (means +/- SE) in N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid-buffered media and 7.23 +/- 0.02 in CO2- HCO3(-)-buffered media, both at extracellular pH 7.4. MTAL tubules exhibited rapid pHi recovery from intracellular acidification. Recovery of pHi was dependent on luminal Na+ (apparent Km = 13.2 +/- 3.2 mM) and was inhibited by amiloride (apparent Ki = 10.6 microM), consistent with the activity of an apical Na(+)-H+ antiporter. Antiporter activity was enhanced by acidification and was diminished at the resting pHi. Recovery from intracellular alkalinization (rapid withdrawal of CO2- HCO3-) was sensitive to the stilbene anion transport inhibitor 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid, Cl(-)-insensitive, and Na(+)-sensitive, consistent with the activity of a Na(+)-(HCO3-)n symporter. Both transporters were significantly involved in steady-state pHi regulation in the presence of CO2- HCO3-. In contrast, the Na(+)-H+ antiporter played the dominant role in steady-state pHi regulation in the absence of CO2- HCO3-.
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PMID:Na(+)-H+ antiporter and Na(+)-(HCO3-)n symporter regulate intracellular pH in mouse medullary thick limbs of Henle. 215 45

Experiments were designed to determine the role of the endothelial cells and the metabolism of arachidonic acid in anoxic contractions of isolated canine basilar arteries. Rings, with and without endothelium, of these arteries were suspended for isometric tension recording; anoxia was induced by switching the mixture gassing the organ chamber from 95% O2-5% CO2 to 95% N2-5% CO2. In rings with endothelium, anoxia evoked increases in tension under basal conditions and during contractions to 5-hydroxytryptamine, uridine triphosphate, prostaglandin F2 alpha, and high K+. Under control conditions, these anoxic contractions were not prevented by alpha-adrenergic and serotonergic antagonists, by apyrase, or by inhibitors of cyclooxygenase. Anoxia prevented endothelium-dependent relaxations evoked by vasopressin and thrombin. In rings without endothelium, anoxia caused increases in tension during contractions evoked by various agonists, and in unstimulated preparations after inhibition of cyclooxygenase. Anoxic contractions were abolished by calcium entry blockers. These observations suggest that anoxic contractions of isolated canine basilar artery can be explained by the release of endothelium-derived contracting factor(s) and the accelerated entry of calcium in the smooth muscle cells, which possibly results from a diversion of arachidonic acid from the cyclooxygenase to the lipoxygenase pathway.
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PMID:Anoxic contractions in isolated canine cerebral arteries: contribution of endothelium-derived factors, metabolites of arachidonic acid, and calcium entry. 243 36

Turtle urinary bladder possesses four ion transport processes: Na+ absorption, H+ secretion, and HCO3- secretion-Cl- absorption. Each transport process is performed by a specific epithelial cell type. Granular cells absorb Na+ but they are not sensitive to antidiuretic hormone (ADH), unlike toad bladder granular cells. alpha-Carbonic anhydrase-rich (CA) cells secrete H+ via an apical H+-adenosinetriphosphatase (ATPase). Under conditions of low CO2 tension, this active pump is contained in the limiting membranes of certain cytoplasmic vesicles. The vesicles fuse with the apical membrane, and H+ pumps are incorporated into that membrane, as physiological conditions demand increased H+ secretion. The stimulus for fusion of these vesicles with the apical membrane appears to be intracellular acidification. beta-CA cells secrete HCO3- and reabsorb Cl-, both processes driven by H+-ATPase in the basolateral membrane in series with an apical Cl- -HCO3- exchanger. Increased intracellular adenosine 3',5'-cyclic monophosphate concentration in beta-cells stimulates net HCO3- secretion and induces an electrogenic component of this flux by activating an apical Cl- channel. This activation accompanies the fusion of an intracellular tubulovesicular network with the apical membrane. The membrane of this network may contain Cl- channels.
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PMID:Turtle urinary bladder: regulation of ion transport by dynamic changes in plasma membrane area. 251 70

The first case of tubal desterilization after Yoon rings through exclusive laparoscopy is reported. Yoon ring tubal segment excision was performed with CO2 laser and coelioscopic scissors, after mesosalpinx haemostasis by ornithine--vasopressin infiltration. Tubal anastomosis was managed with biological glue on an intraluminal guide which was pulled out after 48 h. Follow-up hysterosalpingography 3 months later showed perfect tubal patency. This case proves that complete tubal reversal by exclusive coelioscopy is possible. At present, this procedure is restricted to only one tube during coelioscopic evaluation, preserving, in case of failure, the chance of microsurgery either on the contralateral tube or even on the previously operated one. The advantages of such a technique are those of coeliosurgery: no laparotomy, shortened hospitalization and minimal post-operative adhesions. Since this first case, others have been performed. It is still too early to appreciate the results in terms of intrauterine pregnancy.
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PMID:Tubal desterilization through exclusive laparoscopy. 252 64

Since the first paravertebral blockade was carried out by Sellheim in 1905, this method has proved effective for the isolated blockade of spinal nerves. The efficacy of preoperative intercostal blockade (ICB) in combination with neuroleptanalgesia (NLA) or Pentothal-pentazocine-N2O anesthesia (Pe-Pz) was studied (unilateral analgesia for cholecystectomy). Group 1: NLA; group 2: NLA with ICB; group 3: Pe-Pz; group 4: Pe-Pz with ICB. The analgesic requirement differed significantly between groups 1 (0.33 mg fentanyl) and 2 (0.15 mg fentanyl) and groups 3 (63.5 mg pentazocine) and 4 (31.5 mg pentazocine). There were also significant differences in circulatory responses. The maximum deviation from the initial value at the beginning of the operation in group 1 compared to group 2 was pulse rate + 28.7% vs + 2.4%, mean arterial pressure (Part) + 24.6% vs + 3.1%, and systolic pressure (Psyst) + 33% vs +/- 0%; group 3 compared to group 4: pulse rate + 16.4% vs + 3.2%, Part + 24.5% vs 0.0%, and Psyst + 26.5% vs + 196. The times of action of ICB extended from 7.54 h to 11.33 h for partial analgeisa, time to the first dose of analgesic from 12.3 h to 16.9 h (etidocaine 0.5% and 1% respectively without and with epinephrine). The mean blood levels after 100 mg bupivacaine-CO2 rose to 1.16 micrograms/ml after 5 min and reached a maximum after 15 min (1.29 micrograms/ml) as compared to 0.98 micrograms/ml after addition of ornithine-vasopressin. These values are very much higher than those after the use of bupivacaine-HCl solution. Etidocaine and bupivacaine-HCl have comparable durations of analgesia. Toxicologically, both substances can be applied safely with consideration of all pharmacological data for ICB. Of a total of 3,485 intercostal blockades, 2,775 were applied perioperatively (pre- and postoperatively); 265 were carried out for trauma patients (rib fractures) and 445 for therapeutic indications (herpes zoster neuralgia, tumor pain, costovertebral pain). In 8 blocks 10% ammonium sulfate, in 4 blocks absolute alcohol, and in 19 blocks 5% phenol were used for neurolysis. In 2 cases a marginal pneumothorax was seen, which was resorbed spontaneously (0.06%). Altogether 16,270 single intercostal nerves were blocked. Single-session intercostal blockade can be combined as unilateral analgesia with general anesthesia. This combination is characterized by stable circulatory conditions with avoidance of hypertensive reactions. The long-lasting analgesia allows early mobilization and physiotherapy both postoperatively and posttraumatically in patients with unilateral thoracic and abdominal pain.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[The single intercostal block--surgical and therapeutic indications]. 264 21

To clarify the mechanism of OT secretion of hypothalamus and pituitary origin, in vitro, the guinea pig hypothalamo-neurohypophyseal complex (HNC) was utilized in this study. The HNC, including paraventricular and supraoptic nuclei, was removed and maintained in Eagle's Minimal Essential Medium (pH 7.4) for 7 days at 37 degrees C in a 95% air 5% CO2 environment. The OT content in the hypothalamus and the pituitary remained constant during the period of culture of the HNC. Synthetic OT, hypothalamus or pituitary extracts were eluted separately by ion exchange chromatography and the elution patterns obtained were similar. The stimulation of the HNC with 100mM KCl in the culture caused an increase in OT release. These results suggest that the cultured HNC can be a useful in vitro model for studies of the OT secretion mechanism. After adding several substances to the culture medium, the amount of OT release from the HNC into the culture medium over a 20 minute period, was measured by our own radioimmunoassay. The addition of prostaglandin F2 alpha to the HNC resulted in an increase in OT release while stimulation of D2 or E2 failed to increase. Stimulation of the HNC with vasoactive intestinal polypeptide (VIP) produced an increase in OT release, suggesting the existence of a positive feedback effect of VIP on OT release.
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PMID:[Study on oxytocin secretion from the guinea pig hypothalamo-neurohypophyseal complex (HNC) in organ culture]. 273 60

Sufentanil (mean total dose 2 micrograms/kg) was compared with fentanyl (mean total dose 15 micrograms/kg) as a supplement to 60% N2O anesthesia in 30 adult patients undergoing general surgical procedures. Comparisons were made with respect to stability of hemodynamic variables (heart rate and systolic and diastolic blood pressure), changes in stress hormones (cortisol, antidiuretic hormone, epinephrine, norepinephrine, and dopamine), recovery of alertness and orientation, time to extubation, postoperative analgesia, and measures of respiratory depression (resting end-tidal carbon dioxide tension [PETCO2], CO2 response curve for minute ventilation [delta VE/delta PETCO2]). Hemodynamic variables remained stable and similar in both groups throughout the study. Plasma hormone levels remained similar to baseline in both groups until 1 h postoperatively when epinephrine levels were significantly elevated in both groups (P less than 0.05). Recovery times, including time to extubation, were similar in both groups. Patients given sufentanil had less pain 30 min postoperatively than those given fentanyl, although at 60 min postoperatively pain levels were similar in both groups. Small but significant elevations in resting PETCO2 were seen in both groups postoperatively (P less than 0.05), but postoperative delta VE/delta PETCO2 responses were significantly depressed only in patients receiving fentanyl (P less than 0.05). The results of this study demonstrate that sufentanil-N2O anesthesia is as effective as fentanyl-N2O in attenuating the hemodynamic and hormonal responses to the stress of general surgery. Because continuous intraoperative PETCO2 monitoring was not employed in this study, intraoperative hypocapnea cannot be strictly excluded as a possible influence on the postoperative measures of ventilatory drive.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Comparison of sufentanil-N2O and fentanyl-N2O in patients without cardiac disease undergoing general surgery. 294 75


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