Pancreatitis somatostatin

A new mode of therapy with somatostatin as a prototype may equalize the rates of nutrient entry and removal from the circulation as well as suppress glucagon mediated hyperglycemia. A role for endogenous pancreatic somatostatin as a regulator of nutrient influx from the GI tract in coordination with insulin mediated nutrient disposal has been proposedChanges in endogenous somatostatin availability per se may be responsible for some metabolic abnormalities. 

The conorfamides, isolated from Conus spurius, belong to the RFamide neuropeptide family and may act as an agonist of the FMRF-amide-gated ion channels. In invertebrates, this peptide family has many diverse functions, whereas in the mammalian system they moderate opioid function in the CNS, modulate epithelial Na" " channels, have important cardiovascular effects, and stimulate pancreatic somatostatin secretion. ... 

Tolbutamide, a sulfonylurea drug that increases insulin secretion, also increases the secretion of pancreatic somatostatin. 

Susini, et al. (1986). Characterization of Covalently Cross-linked Pancreatic Somatostatin Receptors, J. Biol. Chem. 261 16738-16743. 

Neuropeptide Y. Neuropeptide Y [82785 5-3] (NPY) (255) is a 36-amiao acid peptide that is a member of a peptide family including peptide YY (PYY) [81858-94-8, 106338-42-5] (256) and pancreatic polypeptide (PPY) [59763-91-6] (257). In the periphery, NPY is present in most sympathetic nerve fibers, particulady around blood vessels and also in noradrenergic perivascular and selected parasympathetic nerves (66). Neurons containing NPY-like immunoreactivity ate abundant in the central nervous system, particulady in limbic stmctures. Coexistence with somatostatin and NADPH-diaphorase, an enzyme associated with NO synthesis, is common in the cortex and striatum. 

The hormone pancreatic polypeptide (PP) is a 36 amino acid peptide, which is closely related to neuropeptide Y and peptide YY PP is mainly found in pancreatic cells distinct from those storing insulin, glucagon or somatostatin. It acts on receptors that belong to the family of neuropeptide Y receptors, particularly on the Y4 subtype. 

Medications aimed at decreasing pancreatic enzyme release (e.g., somatostatin), nasogastric suction, and anticholinergic medications have all failed to show benefit in the treatment of acute pancreatitis. 

Specific hormones Insulin, glucagon, somatostatin, gastrin, pancreatic polypeptide, serotonin, vasoactive intestinal peptide, cholecystokinin... 

Additional impurities, such as glucagon, somatostatin, pancreatic polypeptide and vasoactive intestinal polypeptide, are present in most conventional insulin preparations at lower levels. The presence of such contaminants can impact upon product safety and efficacy in a number of ways. 

Octreotide acetate (Sandostatin) is a synthetic peptide analogue of the hormone somatostatin. Its actions include inhibition of the pituitary secretion of growth hormone and an inhibition of pancreatic islet cell secretion of insulin and glucagon. Unlike somatostatin, which has a plasma half-life of a few minutes, octreotide has a plasma elimination half-Hfe of 1 to 2 hours. Excretion of the drug is primarily renal. 

In their report the researchers describe a culturing technique that can turn mouse embryonic stem cells into cell clusters that resemble pancreatic islets. The clusters inner cells produced insulin, while outer cells produced glucagon and somatostatin, two other proteins typically synthesized by pancreatic cells. Most important, the embryonic stem cell-derived pancreas cells produce insulin in response to glucose, the fundamental role of beta cells that regulate insulin secretion. The major shortcoming of the system at this time is the low levels of insulin production. Refinements in culture technique or drug manipulation may be needed to achieve therapeutic levels. 

Octreotide Somatostatin analog mechanism not certain May alter portal blood flow and variceal pressures Patients with bleeding varices or at high risk of repeat bleeding Reduced endocrine and exocrine pancreatic activity other endocrine abnormalities GI upset... 

Peptide Hormones Peptide hormones may have from 3 to 200 or more amino acid residues. They include the pancreatic hormones insulin, glucagon, and somatostatin, the parathyroid hormone, calcitonin, and all the hormones of the hypothalamus and pituitary (described below). These hormones are synthesized on ribosomes in the form of longer precursor proteins (prohormones),... 

The pancreatic islets consist of four primary cell types alpha (A) cells, which produce glucagon beta (B) cells, which produce insulin delta (D) cells, which produce somatostatin and (F) cells, which produce pancreatic polypeptide. As previously mentioned, this chapter focuses on the functions of insulin and glucagon. The exact physiologic roles of the other pancreatic hormones are not entirely clear. For example, the function of the pancreatic polypeptide released from pancreatic F cells remains to be determined. 

The endocrine islet cells comprise only 1-2% of the pancreatic tissue. They synthesize the hormones insulin, glucagon, somatostatin, and pancreatic polypeptide. Insulin and glucagon maintain glucose homeostasis via their actions on lipid, carbohydrate, and protein metabolism. The pancreas originates from two patches of epithelium in the duodenum during the fifth week of gestation in humans. The endocrine pancreatic cells begin to differentiate very... 

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