Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Short-lasting hypothermia during thiobutabarbital general anaesthesia causes no decrease of the absolute ATP level in the blood and liver of rats. The adenylate energy charge in the tissues is relatively high - 0.86 in the liver and 0.85 in the muscles, which might be an evidence of a significant "energy sparing" during moderate hypothermia (26 +/- 1 degree C). Somatostatin in a dose of 20 micrograms/kg of body weight given to the rats during hypothermia decreased the ATP level, the ATP/ADP ratio and the adenylate energy charge in the studied tissues, especially in the liver, evidencing increased intensity of catabolic processes caused by the inhibitory action of somatostatin on the release of insulin and glucagon, among other hormones, and on the change of the insulin/glucagon ratio.
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PMID:Somatostatin effect on the level of adenyl nucleotides in the blood and tissues of rats during short-lasting hypothermia. 614 95

Cysteamine given three times within 8 h produced severe duodenal and gastric ulcers in female SIV rats. A pentobarbital anesthesia during the first 10 h prevented gastric ulcer formation without affecting duodenal ulcer. An additional 10 h lasting intragastric infusion with 0.6 ml/h Ringer containing 5 mmol/l of a mixture 3: 1 pure taurocholic and glycocholic acid or 20 and 50 mmol/l pure taurocholic acid in 0.2 N HCl did not reverse the protective effect of pentobarbital, e.g. incidence and intensity of gastric ulcer did not change. Treatment with somatostatin significantly reduced the intensity of duodenal ulcer. The inhibition of cysteamine-induced gastric ulcer formation by pentobarbital does not seem to be due to a possible inhibition of duodenogastric reflux but more likely to an inhibition of central nervous stress reactions by anesthesia.
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PMID:Effect of pentobarbital anesthesia and bile acids on cysteamine-induced duodenal and gastric ulcers in rats. 614 97

The role of various bioactive peptides in the control of secretion of hypothalamic somatostatin into the hypophysial portal blood was examined in anesthetized rats. Hypophysial portal blood was withdrawn at a rate of 5.0 microliter/min into a chilled tube through a cannula placed over the stump of the pituitary stalk and segmented every 20 min by air bubbles. Immunoreactive somatostatin (IRS) in the plasma was extracted with acetic acid and acetone and quantified by RIA. Basal levels (mean +/- SE) of plasma IRS in the hypophysial portal blood were 646 +/- 36 and 317 +/- 44 pg/ml in urethane- and pentobarbital-anesthetized rats, respectively. Under urethane anesthesia, injection of synthetic neurotensin into the lateral ventricle at various doses in the range of 0.016--2 microgram/rat caused a significant and dose-related increase of plasma IRS levels in the hypophysial portal blood, and this effect of neurotensin was significantly (P less than 0.05) suppressed by pretreatment with diphenhydramine (1 mg/100 g BW, iv), a histamine receptor blocker. Enhancement of IRS release by neurotensin was also observed in pentobarbital-anesthetized rats. Intraventricular injection of substance P (10 microgram/rat), beta-endorphin (1 and 5 microgram/rat), or [Met5]enkephalin had no effect on the level of somatostatin in the hypophysial portal blood of urethane-anesthetized rats. These results suggest a release of hypothalamic somatostatin into the hypophysial portal blood in response to intraventricular administration of neurotensin, probably by a histaminergic mechanism.
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PMID:Effect of intraventricular injection of neurotensin and other various bioactive peptides on plasma immunoreactive somatostatin levels in rat hypophysial portal blood. 616 24

We have investigated the effect of hypothalamo-pituitary disconnection in the rat on the growth hormone (GH) responsiveness to human pancreatic GH-releasing factor (hpGRF). Adult female rats, sham-operated (sham-op) or bearing a complete mechanical ablation of the mediobasal hypothalamus (MBH-A) were challenged, while under urethane anesthesia, with hpGRF-40 (20,100,500 ng/rat i.v.) at different time intervals after surgery. In sham-op rats only 500 ng/rat of hpGRF-40 stimulated GH release, while in 1-and 7-day MBH-A rats the stimulation also occurred with the lower hpGRF doses and the rise in plasma GH was greater than in sham-op controls. Twenty-one and 42 days after the placing of the lesions the GH response to hpGRF-40 was still present at the 500 ng/rat dose, though it was smaller than in sham-op controls. Evaluation of pituitary GH content demonstrated a progressive and rapid decline starting the first day after the placing of the lesions. These data indicate that GH responsiveness to hpGRF is: enhanced in the anterior pituitary shortly after hypothalamo-pituitary disconnection and, despite a striking reduction of the pituitary GH stores, it is maintained after these lesions. The physiologic growth hormone (GH) releaser in the rat is GH-releasing factor and, recently, a group of peptides has been characterized from human pancreatic tumors (hpGRFs) (1,2) which are potent and specific GH-releasers in both animals and man. The availability of these peptides, which show a high degree of homology with the physiologic rat hypothalamic GRF, offers the unique opportunity to assess somatotrope responsiveness to GRF molecules in rats with hypothalamo-pituitary disconnection. In this study we have first evaluated the GH pituitary responsiveness to increasing doses of hpGRF-40 in rats following mechanical ablation of the medio-basal hypothalamus. These rats, by definition, lack the effect of both central nervous system (CNS) inhibitory (e.g. somatostatin) and stimulatory (e.g. GRF) influences to GH release. With the aim to ascertain how the lack of these two opposing inputs reflects on the secretory capacity of the somatotropes, we also investigated the GH response to hpGRF-40 at different time intervals after the lesioning. In a study in rats with electrolytic lesions of the ventromedial-arcuate region of the hypothalamus Tannenbaum et al had shown persistence of the GH response to huge doses of a hpGRF analog.
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PMID:Growth hormone releasing effect of hpGRF-40 in rats at different time intervals following ablation of the mediobasal hypothalamus. 643 9

A variety of neuropeptides, such as TRH, somatostatin, VIP, Substance P, neurotensin, CCK, gastrin, and opioid peptides, alter secretion of GH and PRL from the pituitary. These actions differ according to the route of administration or with experimental conditions, especially anesthesia. Among these peptides, the most consistent results have been obtained with opioid peptides, which stimulate GH and PRL release. Both beta-endorphin and enkephalins are capable of stimulating GH and PRL release in anesthetized and unanesthetized, freely moving rats. The effect is blocked by naloxone, an opiate receptor antagonist. GH secretion induced by opioid peptides seems to be mediated by an alpha-adrenergic mechanism, since treatment with DDC and fusaric acid, which are dopamine-beta-hydroxylase inhibitors, reserpine, and phenoxybenzamine which is an alpha-adrenergic blocking agent, blunted GH secretion. However, pimozide, a dopamine receptor antagonist, and propranolol, a beta-adrenergic blocking agent, were without effect. On the other hand, basal PRL secretion was augmented by pimozide, suggesting the possible involvement of dopamine. It is also possible that serotonin is involved in the GH and PRL release induced by opioid peptides. The physiological significance of opioid peptides in regulating GH and PRL secretion is still unclear. Contradictory results (12,25) have been obtained concerning the effect of naloxone on basal or stimulated GH and PRL secretion in rats, monkeys and humans when tested by the continuous blood sampling method, which rules out the erroneous evaluation of results caused by episodicity of plasma hormone levels. Further studies should clarify the physiological role of opioid peptides in regulating pituitary function.
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PMID:Effect of CNS peptides on hypothalamic regulation of pituitary secretion. 701 Sep 47

Changes in plasma potassium ([K+]p) and insulin levels were monitored during K+ infusion in awake and anesthetized nephrectomized, splenectomized dogs. In dogs studied while anesthetized with pentobarbital, the increase in [K+]p was linear, reflecting a nearly constant rate of cellular uptake of the infused K+. In contrast, in dogs studied 18 h after nephrectomy while awake, [K+]p oscillated during infusion, reflecting an inconstant rate of cellular K+ uptake. Although these oscillations in [K+]p were associated with parallel oscillations in plasma insulin levels (suggesting the possibility of a physiological feedback control loop involving K+ and insulin), when the oscillations in insulin levels were blunted by somatostatin infusion or abolished by pancreatectomy plus insulin replacement, oscillations in [K+]p persisted and the average rate of cellular K+ uptake was not diminished. The observed oscillations of [K+]p during K+ infusion suggest the possibility of regulatory control of cellular K+ uptake within the pathophysiologic range of [K+]p. The putative control system is independent of and quantitatively more important than K+-induced insulin secretion and is obscured by pentobarbital anesthesia.
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PMID:Oscillations of plasma K+ and insulin during K+ infusion in awake anephric dogs. 704 74

We have studied the analgesic effects of somatostatin during surgery and its influence on the plasma glucose levels and the liver enzyme profile in 40 ASA 1 or 2 patients undergoing surgery for carcinoma of the gastrointestinal tract. Each patient received either somatostatin bolus 3.5 micrograms.kg-1 intravenously plus an infusion of somatostatin 3.5 micrograms.kg-1.h-1, or sodium chloride 0.9% as a placebo in a double-blind manner. Anaesthesia was induced with propofol 1 mg.kg-1 followed by a continuous infusion of propofol in a stepwise declining regimen. Vecuronium was used for muscular relaxation. Fentanyl 100 micrograms was administered intravenously in bolus doses for analgesia during surgery as required. Blood samples were taken at 10 min pre-induction, 5 min postintubation, 5, 30, 60, 120 min postincision and 30 min post-recovery for plasma glucose levels. Blood samples were also taken at 10 min pre-induction, 120 min postincision and 24 h postoperatively for liver enzymes. The total requirement for fentanyl in the control group was significantly higher (p < 0.001) than in the group that received somatostatin. Eight out of 20 patients in the study group required no additional analgesia intra-operatively. The changes in blood glucose values followed the same pattern in both groups. There was a tendency for liver enzymes to increase in both groups. Although this increase was less in the study group, this change was not statistically significant.
Anaesthesia 1995 Jul
PMID:Somatostatin and total intravenous anaesthesia. Assessment of analgesic requirements during surgery and the effects on liver enzymes. 765 56

The importance of glucagon on postoperative changes in hepatic amino-nitrogen conversion were investigated in six patients undergoing elective cholecystectomy for uncomplicated gall stones. Patients were given infusions of somatostatin (bolus of 6 micrograms/kg followed by continuous infusion of 6 micrograms/kg/h) from induction of anaesthesia to the end of investigation, the first postoperative day (30 hours). Controls were 16 patients undergoing the same procedures omitting the somatostatin infusion. In all patients blood concentration and plasma clearance of total alpha-amino-nitrogen, and amino acid stimulated rate of urea synthesis were measured. Elective cholecystectomy decreased blood alpha-amino-nitrogen concentration from mean (SEM) 2.9 (0.2) to 2.4 (0.1) mmol/l (p < 0.05), increased the clearance of total alpha-amino-nitrogen from 5.2 (0.3) to 6.6 (0.3) ml/s (p < 0.05), and increased the rate of amino acid stimulated urea synthesis from 27 (1) to 37 (2) mumol/s (p < 0.05) pointing to increased hepatic removal of amino-nitrogen at expense of plasma amino-nitrogen. Infusion of somatostatin prevented increase of glucagon for 24 hours after surgery, and prevented the negative changes in postoperative nitrogen homeostasis resulting from the postoperative changes in hepatic nitrogen conversion, suggesting glucagon as mediator. The exact mechanism remains in doubt, however, because of the multiple effects of somatostatin.
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PMID:Somatostatin prevents the postoperative increases in plasma amino acid clearance and urea synthesis after elective cholecystectomy. 779 29

Pharmacological doses of growth hormone (GH) in humans and rats increase plasma and muscle glutamine values. As major surgery results in a physiological rise in serum GH concentration, we investigated whether this physiological increase in GH altered glutamine metabolism. Eighteen patients undergoing coronary artery bypass graft (CABG) surgery were randomly assigned to receive somatostatin, 100 micrograms subcutaneously at induction of anaesthesia and 8 hourly for 48 h, or placebo. Somatostatin effectively blocked the physiological surge of GH following injury but did not affect plasma or muscle glutamine concentrations, which fell significantly in both groups. Plasma glutamine decreased by 31% (P < 0.01) and 28% (P < 0.01) in the control and somatostatin groups respectively. Muscle glutamine was reduced 45% (P < 0.001) in the control group and 50% (P < 0.001) in the somatostatin group. There was no difference in muscle or circulating glutamate, alanine or branched chain amino acid concentrations or in metabolite values between the somatostatin-treated patients and the control group. There was no relationship between the GH response to surgery and glutamine metabolism following major surgery.
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PMID:Growth hormone suppression and glutamine flux associated with cardiac surgery. 782 Sep 81

In the severe crisis of carcinoid syndrome the flush is usually accompanied by hypotension and occasionally shock. Injection of octreotide, the long-acting analog of somatostatin, usually prevents or aborts this vasomotor reaction. A small minority of carcinoid syndrome patients manifest hypertension during their crises and little has been reported in the literature on their management. We present the first case reports of the response of patients with hypertensive carcinoid crisis to treatment with octreotide. The world literature contains reports of 20 prior cases of hypertensive carcinoid crises occurring in association with the stress of surgery and anesthesia. Review of these cases reveals no common feature, other than hypertension, that might clearly distinguish them from the typical hypotensive carcinoid syndrome patient. It is hypothesized that the mechanism of action of octreotide correcting the blood pressure changes in all carcinoid crises is via its known inhibition of vasomotor product release from the tumor and blocking receptors for these substances. We suggest that hypertensive as well as hypotensive carcinoid crises respond to octreotide and that this agent should be considered for prophylactic and emergency use in all carcinoid syndrome patients prior to and during anesthesia and surgery.
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PMID:Octreotide treatment of carcinoid hypertensive crisis. 796 29


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