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)

This work was undertaken to study the effect of glucose on pancreaticoduodenal and peripheral venous somatostatin-like immunoreactivity (SLI) levels in dogs. Our experiments were performed in normal and alloxan diabetic dogs, conscious or anesthetized. The response of somatostatin was studied following intravenous (0.2 g/kg) or oral (1 g/kg) glucose administration. SLI levels were assayed in peripheral venous blood and in superior pancreaticoduodenal venous blood. An interplay of the cholinergic nervous system was challenged both after oral and intravenous glucose load by a prior administration of atropine sulfate (0.2 mg/kg i.v.). Our results show that (a) peripheral venous SLI levels do not reflect pancreatic D-cell activity in alloxan diabetic as in normal animals. (b) Increase of peripheral venous SLI level after oral glucose is under cholinergic nervous system control. (c) In alloxan diabetic dogs, the response of pancreaticoduodenal venous SLI to intravenous glucose was decreased, whereas peripheral SLI response to oral glucose was increased.
Pancreas 1987
PMID:In vivo study of glucose-induced somatostatin secretion: comparison in normal and alloxan-diabetic dogs. 289 26

Labeled somatostatin binding to pancreatic acinar membranes was examined to investigate how pancreatic secretagogues regulate somatostatin receptors in the pancreas. Pretreatment of pancreatic acini at 37 degrees C for 120 min with not only pancreatic secretagogues, such as carbachol and bombesin, but also vasoactive intestinal peptide (VIP) and secretin reduced subsequent labeled somatostatin binding to the acinar membranes in a dose-dependent manner. The inhibitory effects of these secretagogues on labeled somatostatin binding were also time dependent. Both types of secretagogues maximally reduced subsequent somatostatin binding when acini were incubated with them for more than 120 min. However, the degree of the inhibition was greater with carbachol or bombesin than VIP or secretin; the former secretagogues reduced the binding to 40-45%, and the latter to 75-80% of a control, respectively. These pancreatic secretagogues had no inhibitory effect on somatostatin binding when added directly to the binding media. Furthermore, the inhibitory effect of carbachol was attenuated by the presence of 1 mM EDTA in media for pretreatment, suggesting that intracellular pathways activated by pancreatic secretagogues may be responsible for somatostatin receptor modulation. Interestingly, when combined with VIP, pretreatment of acini with carbachol produced an additive inhibition of labeled somatostatin binding to the membranes. Results, therefore, suggest that somatostatin binding to its receptors in the pancreas may be regulated via two functionally distinct intracellular pathways.
Pancreas 1988
PMID:Pancreatic secretagogues regulate somatostatin binding to its receptors on rat pancreatic acinar membranes. 289 51

Calcitonin gene-related peptide (CGRP)- and somatostatin (SRIF)-containing cells were identified by immunocytochemical techniques in pancreatic islet cells of the rat. CGRP-containing cells were found primarily in the peripheral portion of the pancreatic islets. In addition, CGRP-containing cells also contained somatostatin, which identifies the islet CGRP-containing cells as D cells. In the present study, we also tested the effect of CGRP on gastrin-releasing peptide (GRP; 10(-9) M)- or cholecystokinin (CCK-8, 10(-9) M)-stimulated release of insulin from isolated rat islets in vitro. At concentrations of 10(-8)-10(-11) M, CGRP inhibited GRP- and CCK-8-stimulated release of insulin significantly when compared with GRP or CCK-8 alone. At the lowest concentration of CGRP (10(-11) M), the inhibitory effect of CGRP on CCK-8-stimulated release of insulin was statistically significant (p less than 0.05) and exceptionally potent (65-90% inhibition). We have also found that CGRP does not stimulate the release of SRIF from isolated islet cells. These findings suggest that CGRP may play a regulatory role in the release of insulin.
Pancreas 1988
PMID:Colocalization of calcitonin gene-related peptide and somatostatin in pancreatic islet cells and inhibition of insulin secretion by calcitonin gene-related peptide in the rat. 289 52

Five patients with Zollinger-Ellison syndrome (ZES) have been treated during 9-12 months with long-acting somatostatin (SMS 201-995). Basal acid output presented a sustained decrease in 4 of 5 cases, below 10 mmol/h in three patients, allowing ranitidine discontinuation. No escape phenomenon was observed. Maximal acid secretion progressively decreased, suggesting an SMS antitrophic effect. Serum gastrin level was affected in a greater extent, showing a mean 87% decrease throughout the treatment period. Thus three patients kept normal serum gastrin levels in the long-term; one escaped to SMS after 9 months. Associated endocrine neoplasia were poorly influenced by SMS. No convincing evidence of tumor size variation was noted. Tolerance of SMS was excellent in the five patients. SMS' antitrophic and antigastrin properties could be of great interest in long-term management of ZES.
Pancreas 1988
PMID:Long-acting somatostatin (SMS 201-995) in the management of Zollinger-Ellison syndrome: evidence for sustained efficacy. 289 87

It is known that cholecystokinin (CCK) stimulates islet hormone secretion under a variety of experimental conditions. Since CCK occurs in several different molecular forms, with 58, 39, 33, 12, 8, or 4 amino acid residues, the question has evolved as to which is the shortest active form of CCK. We therefore investigated the influences of the C-terminal octapeptide of CCK, CCK-8 (sulfated form) and of the C-terminal tetrapeptide, CCK-4, on the secretion of insulin, glucagon, and somatostatin from the pig pancreas in vivo by infusing each of the two peptides into the superior pancreatic artery. We found that islet hormone secretion increased promptly upon infusion of both CCK-8 and CCK-4. Thus, the secretion of insulin was stimulated from 51 +/- 12 to 295 +/- 70 microU/min during the first 2 min after injection of CCK-8 and from 40 +/- 12 to 240 +/- 78 microU/min after injection of CCK-4. Similarly, the secretion of glucagon was stimulated from 240 +/- 45 to 357 +/- 38 pg/min after CCK-8 and from 282 +/- 44 to 335 +/- 43 pg/min after CCK-4, and somatostatin secretion was stimulated from 112 +/- 7 to 226 +/- 12 pg/min by CCK-8 and from 105 +/- 11 to 246 +/- 16 pg/min by CCK-4. With regard to the efficiency to stimulate the secretion of these three islet hormones, CCK-8 and CCK-4 were equipotent. We conclude that in pigs, CCK-8 and CCK-4 both stimulate the secretion of insulin, glucagon, and somatostatin from the pancreas in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)
Pancreas 1988
PMID:Cholecystokinin (CCK)-4 and CCK-8 stimulate islet hormone secretion in vivo in the pig. 289 79

These studies were undertaken to assess the effects of chronic administration of cerulein plus secretin, every 8 h for 10 days on fluid, protein, and somatostatin-like immunoreactivity (SLI) outputs in rat pancreatic juice. Pancreatic secretion was studied with conscious, cannulated rats, during infusion of precollected pancreatic juice to the rat intestine. Volume output reached a plateau of 5.2 ml/210 min after 3 days of treatment. Protein secretion steadily increased up to 218 mg/210 min after 5 days, decreased to 118 mg/210 min by day 7, and rose again to 281 mg/210 min after 10 days. The SLI release increased stepwise with a first plateau after 3 days at 493 ng/210 min; values between 983 and 562 ng/210 min were observed between days 4 and 7 with a third plateau at 1,887 ng/210 min between days 8 and 10. Peak levels of volume and protein occurred between 30 and 90 min following each daily stimulation. In the early days SLI output reached its peak 3.5 h after stimulation, whereas at the end of treatment, synchronous secretion of protein and SLI was observed. These data indicate that important modifications occur in the rate of secretion of protein and SLI in the pancreatic juice in the course of chronic administration of cerulein plus secretin.
Pancreas 1988
PMID:Secretion of protein, fluid, and immunoreactive somatostatin in rat pure pancreatic juice: adaptation to chronic cerulein and secretin treatment. 290 20

Terbutaline, a selective beta 2-adrenoreceptor agonist, has recently been advocated as a potential agent for treating patients with pancreatic fistulae. In the present study, we attempted to quantify the presumed effects of terbutaline on exocrine pancreatic secretion in humans and to characterize possible mechanisms of action. In six healthy volunteers, the pancreas was stimulated by infusion of graded doses of secretin (15.5-250 ng/kg/h) or by infusion of secretin (15.5 ng/kg/h) plus graded doses of caerulein (3.3-30 ng/kg/h). The experiments were repeated in each subject without and with administration of terbutaline. Pancreatic secretion was assessed by a marker perfusion technique and plasma somatostatin and pancreatic polypeptide (PP) levels by radioimmunoassay. Terbutaline had no significant effect on secretin-stimulated pancreatic secretion, but significantly inhibited caerulein-stimulated pancreatic fluid secretion and trypsin output. Plasma somatostatin and PP levels were not affected by terbutaline. The inhibitory effect required the administration of pharmacologically large doses of terbutaline. We conclude that the weak inhibitory effect of terbutaline on exocrine pancreatic secretion is not mediated via somatostatin nor PP and that our data do not support a major role for beta-adrenergic mechanism as regulator of pancreatic secretion.
Pancreas 1988
PMID:Mechanisms of terbutaline-induced inhibition of exocrine pancreatic secretion in humans. 290 21

Antisera and radioimmunoassays against five different regions of prosomatostatin (proSS) were used for chromatographical analysis and for immunohistochemical mapping of the products of proSS in the pig pancreas. Secreted products of proSS were studied by analysis of effluent from isolated perfused pig pancreas obtained during isoproterenol stimulation. All cells that were stained with one antiserum also stained with the other antisera. Immunoreactive nerves were not observed. Isoproterenol increased equally the secretion of proSS 20-36, proSS 65-76, and proSS 79-92 immunoreactivity. The major molecular forms identified in pancreatic extracts and released from the pancreas were proSS 79-92; proSS 65-76; an N-terminally extended form of proSS 65-76; and two larger forms comprising the proSS 20-36 sequence (but not the 1-13 sequence) with and without the proSS 65-76 sequence. ProSS 1-10, 1-32 and 65-92 (somatostatin 28) were not identified.
Pancreas 1988
PMID:Processing and secretion of prosomatostatin by the pig pancreas. 290 23

Plasma somatostatin response to food and the administration of the long-acting somatostatin analogue SMS 201-995, as well as pituitary responses to insulin-induced hypoglycemia, growth hormone-releasing hormone (GHRH) and thyrotropin-releasing hormone (TRH), were assessed in a 60-year-old woman with biopsy-proven metastatic somatostatinoma. SMS 201-995 alone did not change plasma somatostatin-like immunoreactivity (SRIF), but levels of low-molecular-weight forms (SRIF-14 and SRIF-28) more than doubled in response to a standard meal. This postprandial response was not affected by pretreatment with SMS 201-995. Although a growth hormone response to insulin-induced hypoglycemia and supramaximal GHRH was absent, the patient's thyroid-stimulating hormone response to TRH was normal. These results suggest that somatostatin analogues may not influence tumor autonomy and that a SRIF response to food may contribute to early satiety in patients with somatostatinoma. In addition, the long-term use of somatostatin analogues to suppress hormone production by other peptide-secreting tumors may not have predictable results.
Pancreas 1988
PMID:A case of somatostatinoma: responses to food and SMS 201-995 administration. 290 26

A new technique to obstruct the pancreatic ducts was developed by injecting zein solution into the common bile duct of the rat. Four weeks after the injection, the fate of the endocrine pancreas was investigated by studying (a) pancreatic content of four pancreatic hormones, (b) histology and immunohistochemistry of the pancreas, (c) i.v. glucose tolerance and i.v. insulin tolerance tests for monitoring plasma glucose, insulin, and pancreatic polypeptide (PP) levels in vivo, and (d) in vitro perifusion of pancreatic tissue slices to assess insulin and PP secretion. In zein-injected rats, the total pancreatic content of insulin, glucagon, PP, and somatostatin was reduced to 80, 70, 40, and 20%, respectively, of the corresponding controls. In response to insulin-induced hypoglycemia, the plasma PP levels rose to about one-half that of the controls. By contrast, perifused zein-injected rat pancreases released several times more PP than the controls in response to carbachol stimulation. In zein-injected rats, total pancreatic protein was reduced to 20% of the controls and pancreatic amylase was almost absent, reflecting practically complete loss of acinar tissue. Thus, this experimental model appears to be suitable for producing chronic pancreatic insufficiency in the rat and provides a useful model for studying both endocrine and exocrine functions in the small rodent.
Pancreas 1988
PMID:Endocrine pancreas in the rat model of exocrine pancreatic insufficiency. 305 70


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