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

The effect of the presence of food in the intestinal lumen on fluid transport by an intestinal loop isolated from nutrients is debatable and seems to be species dependent. The aim of the present study was to investigate this effect in humans. Fluid and ion transport by a 30-cm-long jejunal loop was measured by the perfusion of a plasmalike electrolyte solution below an occlusive balloon inflated at the angle of Treitz. At the same time, the duodenum was infused at the papilla by saline (control period) or one of the following solutions (test period): protein hydrolysate, starch hydrolysate, lipids, or mixed nutrients. The four solutions (pH 7; 300 mosmol/L; 540 kcal/L) were infused in 6 normal subjects in a randomized order. In 6 further subjects, two other loads of intraduodenal lipids (120 and 1080 kcal/L) were tested according to a similar protocol. Blood samples were taken serially for radioimmunoassays of gastrin, secretin, cholecystokinin, pancreatic polypeptide, gastric inhibitory polypeptide, vasoactive intestinal polypeptide, motilin, and somatostatin. Intraduodenal mixed nutrients, proteins, and lipids significantly reduced water and ion jejunal net absorption or induced a net secretion (without dose-effect relationship for lipids) and stimulated plasma cholecystokinin, pancreatic polypeptide, and gastric inhibitory polypeptide. Intraduodenal lipids also stimulated circulating levels of gastrin and vasoactive intestinal polypeptide. Intraduodenal sugars did not change jejunal fluid and ion transport and significantly increased plasma gastric inhibitory polypeptide. Covariance analysis showed transjejunal fluid movements to be linked with plasma levels of cholecystokinin. We conclude that an intraduodenal mixed meal exerts a secretory effect on a jejunal loop isolated from the nutrients and that this effect is due to the lipid and protein content of the meal; our data are compatible with a mediation of this phenomenon by cholecystokinin.
 ...
PMID:Jejunal secretory effect of intraduodenal food in humans. A comparison of mixed nutrients, proteins, lipids, and carbohydrates. 257 68

During the course of studies of the effects of pantethine, a cysteamine precursor known to deplete tissue concentration of immunoreactive somatostatin, we observed that the subject rats continued to eat despite marked distension of the stomach. To determine whether this effect was caused by drug-altered food intake, we have measured food and water intake in pantethine-injected rats in the fed and fasting state. In three separate experiments, rats allowed free access to food until the morning of study showed significant increased food intake accompanied by an increased stomach content (at 4 hr) of both food and water following the IP injection of pantethine. In one experiment, intake at 3 hours was 0.60 g/100 g b.wt. (pantethine dose 0.74 g/kg b.wt.) and 0.64 g/100 g b.wt. (pantethine dose 1.47 g/kg b.wt.) compared with 0.24 g/100 g b.wt. in saline-treated animals (p less than 0.05). In contrast, pantethine, 1.47 g/kg b.wt., when administered to overnight-fasted rats, significantly inhibited food intake (3-hr intake 1.54 +/- 0.16 g/100 g b.wt. in rats injected with pantethine 1.47 g/kg b.wt. as compared with 3.3 +/- 0.21 g/100 g b.wt. in saline-injected controls). The intake-stimulating effect of pantethine in ad lib-fed rats was not demonstrable when the drug was administered shortly before the "lights out"-induced feeding at night. These findings indicate that pantethine, a cysteamine precursor, stimulates food intake in satiated rats, depending upon the stage of circadian rhythm, but is inhibitory to intake in fasted animals. We postulate that the effects are mediated directly or indirectly through the disinhibition of central appetite-regulating somatostatinergic pathways but, since cysteamine also inhibits dopamine-beta-hydroxylase, an effect on depletion of appetite-regulating central catecholamines cannot be excluded.
 ...
PMID:Pantethine, a somatostatin depleting agent, increases food intake in rats. 258 1

The effects of cysteamine-induced reductions of somatostatin-like immunoreactivity (SLI) on spatial learning, passive avoidance, and locomotor activity were examined in adult Sprague-Dawley rats. Cysteamine hydrochloride (100 mg/kg, s.c.) produced 54% and 50% reductions in SLI in cortex and hippocampus, respectively, and impaired escape latencies and spatial probe behavior in the Morris water task. Although cysteamine-treated rats displayed hypoactivity in the activity boxes, their swim speed in the Morris water task was unaffected. Cysteamine did not impair passive avoidance retention when administered immediately following training or prior to daily retention testing. These results suggest a role for somatostatin in spatially-mediated behaviors in rats.
 ...
PMID:Morris water task impairment and hypoactivity following cysteamine-induced reductions of somatostatin-like immunoreactivity. 259 42

The chemistry, pharmacology, pharmacokinetics, clinical uses, adverse effects and drug interactions, dosage, availability and cost, and indications for use of octreotide, a new synthetic analogue of the peptide hormone somatostatin (SS), are reviewed. Like SS, octreotide suppresses secretion of pituitary growth hormone (GH) and thyrotropin and decreases release of a variety of pancreatic islet cell hormones including insulin, glucagon, and vasoactive intestinal peptide (VIP). Octreotide also reduces splanchnic blood flow, gastric acid secretion, GI motility, and pancreatic exocrine function and alters the absorption of water, electrolytes, and nutrients from the GI tract. The elimination half-life of i.v. octreotide is 72-98 minutes, compared with 2-3 minutes for i.v. SS. Usual administration of octreotide is by the i.v. or s.c. route. Octreotide has been studied in the treatment of hormone-secreting pituitary tumors and pancreatic islet cell tumors. Octreotide therapy lowers GH secretion and improves clinical symptoms in patients with acromegaly and may suppress clinical symptoms to a greater degree than bromocriptine. Patients with carcinoid syndrome and VIP-secreting tumors (vipomas) have had substantial improvement in clinical symptoms with administration of octreotide. This agent does not appear to be effective in the treatment of nonvariceal upper GI bleeding and acute pancreatitis; its relative usefulness in the treatment of variceal bleeding is not established. Adverse effects associated with octreotide therapy generally have been mild, including pain or burning at the injection site, abdominal pain, and diarrhea. Octreotide has been shown to interfere with absorption of oral cyclosporine. Standard initial therapy is octreotide acetate 50-100 micrograms s.c. every 8-12 hours, with titration based on clinical and biochemical effects. Up to 3000 micrograms/day of octreotide acetate has been administered to patients with acromegaly without serious adverse effect. Octreotide is marketed under the brand name Sandostatin and is available in 1-mL ampuls containing 50, 100, and 500 micrograms of octreotide acetate. Because the conditions for which octreotide appears to be most effective are uncommon, the drug should be considered for addition to the formulary in tertiary-care institutions only; addition of octreotide to the formulary of a community hospital is probably unnecessary. The synthetic analogue octreotide is longer acting and more specific in pharmacologic action than SS.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Octreotide, a new somatostatin analogue. 265 11

A host of chemically diverse compounds have antidiarrheal potency, however, only a fraction of these agents has gained clinical acceptance. But regardless of their therapeutic status, the effects of these drugs have enhanced our understanding of the physiology and pathophysiology of the intestinal mucosa. Fluid- and electrolyte substitution are the primary therapeutic measures in severe diarrhea, for that purpose oral rehydration using glucose-sodium solutions has proven simple and effective. In addition gut-selective opiates, for instance loperamide, are indicated. Opiates not only decrease propulsive motor activity of the bowel but also increase intestinal water and electrolyte absorption, both effects are neuronally mediated. Antimicrobial drugs are necessary in only a small fraction of patients with diarrhea. Experimental findings have indicated possible future candidates for treatment of diarrhea: Besides opiates and glucose-electrolyte solutions water and electrolyte absorption is enhanced by alpha 2-adrenergic agents, corticosteroids, and somatostatin. Inhibitors of electrolyte secretion include phenothiazines and opiates, possibly because of binding to calcium-calmodulin, calcium-channel blockers, membrane-stabilizing agents for instance propranolol and inhibitors of prostaglandin-synthesis such as non-steroidal antirheumatic agents.
 ...
PMID:[Antidiarrheal agents: tools and therapeutic agents]. 265 88

Ten male healthy volunteers were studied in order to determine whether the synthetic somatostatin analogue Sandostatin (SMS 201-995) has effects similar to those of natural somatostatin on renal water and electrolyte excretion. The study was carried out in three separate placebo-controlled randomized double-blind cross-over trials. The subjects received single sc injections of 100 micrograms Sandostatin and placebo under conditions of mild diuresis (trial 1), water load with enhanced diuresis (trial 2), and water load with exogenous lysin-vasopressin (5 IU sc) induced antidiuresis (trial 3). The following parameters were measured: urine flow rate, serum and urine osmolalities, osmolar clearance, free water and creatinine clearances, excretion rates of sodium, potassium, calcium, chloride, and phosphate, and immunoreactive insulin. A marked antidiuretic effect was observed within 2 h after dosing in all three trials. Urine flow rates were reduced by 45% in trial 1 and by 29 and 31% in trials 2 and 3, respectively (all P less than 0.05). There were no differences in effects on serum and urine osmolalities between Sandostatin and placebo. Osmolar clearance was significantly reduced in trial 1 (P less than 0.01). Free water clearance significantly decreased only in trial 2 (P less than 0.05). Sodium excretion decreased by 49, 48 and 67%, respectively, the differences being significant in trials 1 and 3 (P less than 0.05). Calcium excretion decreased by 66, 70 and 54% (all P less than 0.001). Chloride excretion decreased by 28, 22 and 44%, the differences being significant in trials 2 and 3 (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Antidiuretic effect of Sandostatin (SMS 201-995) in healthy volunteers. 265 54

The effect of a long acting somatostatin analogue SMS 201-995 on stomal effluents in patients with severe short bowel syndrome was investigated in a double blind placebo controlled balance study. Six patients, five with Crohn's disease and one with radiation enteropathy were studied. Five patients had a jejunostomy and one an ileostomy. The patients had a normal food intake, but because of severe malabsorption had received home parenteral nutrition for several years. Faecal mass was reduced (p less than 0.005) and intestinal net sodium absorption was increased (p less than 0.005) by intravenous infusion of SMS 25 micrograms/h. Net absorption of potassium, calcium, magnesium phosphate, zinc, nitrogen and fat was not influenced. Subcutaneous injections of 50 micrograms SMS every 12 hours had a similar effect on net intestinal absorption of sodium and water. Four patients continued with a five to six months open follow up study when subcutaneous SMS in the same dose was administered by the patients at home. The effect on faecal sodium loss persisted, but in one patient faecal mass gradually increased and finally exceeded pretreatment values. SMS may decrease net absorption of water and sodium following reduced secretion of digestive juices rather than by increasing absorptive capacity. SMS may be useful as an antidiarrhoeal drug in patients with high output jejuno- or ileostomies, but in patients who need permanent parenteral nutrition the effect is too small to significantly alter management.
 ...
PMID:Effect of a long acting somatostatin analogue SMS 201-995 on jejunostomy effluents in patients with severe short bowel syndrome. 231 26

Pretreatment with a somatostatin analogue, octreotide (SMS 201-995), prevents postprandial blood pressure reduction in the elderly. We hypothesized that this beneficial effect on blood pressure is caused by an octreotide-induced suppression of insulin secretion. We studied the effects of octreotide and insulin administration on the course of blood pressure after oral glucose loading in 10 healthy hypertensive old persons (mean age 73 +/- 3 years). Octreotide was given in a dose of 50 micrograms subcutaneously (sc) (time = -30 minutes). Insulin was given sc in a dose of 0.3 U/kg body weight (time = -10 minutes) and glucose was given orally in a dose of 75 g in 300 mL water (time = 0 minutes). Plasma insulin concentrations remained essentially unchanged after placebo and rose to a maximum level of 58 +/- 6 mU/L following insulin administration. The course of blood pressure was not different following glucose loading with high or low plasma insulin levels. These data indicate that the effects of octreotide on postprandial blood pressure reduction in the elderly are unrelated to the inhibition of insulin secretion.
 ...
PMID:Influence of octreotide (SMS 201-995) and insulin administration on the course of blood pressure after an oral glucose load in hypertensive elderly subjects. 268 50

A 27 month old girl with congenital microvillus atrophy received two courses of SMS 201-995, a synthetic long acting analogue of native somatostatin, in an attempt to decrease profuse secretory diarrhoea. During the first trial at 13 months of age fluid and electrolytes administered by parenteral infusion were decreased as measured by water and faecal electrolyte losses. During the second trial of SMS 201-995 at 19 months fluid and electrolyte input were held constant for 14 days. Stool volume declined from 275 ml/kg to 161 ml/kg. Reductions in output of stool electrolytes (Na+, K+, Cl-) were accompanied by an increase in urine fluid output and increased excretion of urinary Na+. Subsequent administration of SMS 201-995 for a nine month period was not associated with adverse side effects or an impairment of growth velocity. These findings suggest that SMS 201-995 may be useful therapy in infants with high output diarrhoea as a result of congenital microvillus atrophy.
 ...
PMID:Clinical response to the long acting somatostatin analogue SMS 201-995 in a child with congenital microvillus atrophy. 275 84

1. Preliminary, general chemical characteristics of substances in artificial sea water (ASW) washed through stimulated body wall (SBW) and in hemolymph taken from noxiously stimulated animals (SHL) were consistent with those of classical neurotransmitters, amino acids, and small- to medium-sized peptides. 2. 5-Hydroxytryptamine (5HT) and acetylcholine (ACh), unlike SBW and SHL, caused relaxation when perfused into isolated body wall. FMRFamide produced a biphasic response--brief contraction followed by prolonged relaxation. 3. Small cardioactive peptide (SCPB) caused body wall contractions similar to those produced by SBW and SHL, except that SCPB contractions displayed more desensitization and were completely blocked by 30 mM CoCl2. SCPB and SBW contractions were synergistic. 4. Dopamine caused persistent body wall contractions similar to those of SBW and SHL. Dopamine contractions were reduced but not blocked by 30 mM CoCl2. Unlike SBW activity, dopamine activity was reduced by alkalinization. 5. Glutamate and taurine produced strong but usually short-lasting body wall contractions. Adenosine, octopamine, arginine vasotocin, and cholecystokinin (CCK-8) caused weak or variable contractions. Met-enkephalin and somatostatin caused no obvious body wall responses. 6. When superfused over the fully sheathed abdominal ganglion, FMRFamide, met-enkephalin, glutamate, aspartate, and taurine reduced the magnitude of the gill-withdrawal reflex elicited by siphon nerve stimulation. 7. Taken together with earlier results, these data suggest a preliminary framework for trauma signal pathways. It is proposed that stress hormones (perhaps including FMRFamide, SCPs, 5HT, and dopamine) are released into hemolymph from neuroendocrine cells. Effective amounts of active intracellular solutes such as amino acids may also be released by extensive cellular rupture. Various humoral signals produce slow effects that contribute to hemostasis, balling up, increased cardiac output, and reflex suppression.
 ...
PMID:Humoral factors released during trauma of Aplysia body wall. II. Effects of possible mediators. 276 Feb 88


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>