Uroguanylin And Serotonin Secretion From The Isolated Rate Jejunum: Vascular And Luminal Release.

Leptin is an adipocyte produced peptide that controls food intake and the energy expenditure.Many of its effects are mediated centrally via hypothalamic receptor but also peripheral effects of leptin such as gastroprotection has been recently described and found to contribute to action of CCK on the stomach.Leptin receptors and leptin were detected recently in the.pancreas.CCK was found to increase the plasma leptin but this leptin seems to originate mainly from stomach where it inhibits gastric secretion but its role control of pancreatic secretion has not been studied.The aim of this study was to evaluate the effect of leptin on pancreatic secretion in vivo in rats surgically with pancreatic fistulas and in vitro using dispersed pancreatic acini on exocrine.After preliminary administration of various doses ofleptin, the standard dose of (10 I-tglkg-h, s.c.), that inhibited gastric secretion for testing pancreatic secretion.The pancreatic secretory response to sham feeding, ordinary feeding and pancreatic juice diversion were significantly inhibited by this dose of leptin by about 29%, 60% and 82%, respectively.In isolated pancreatic acini, obtained from the rat by collagenase digestion, increasing concentrations of leptin (10•1~-1O.7M)added to incubation medium failed to affect significantly basal secretion but produced dose-dependent inhibition of amylase release stimulated by submaximal dose of caerulein (1O_ 12M) but not by urecholine (lO•5M).We conclude that leptin inhibits stimulated pancreatic secretion both in vivo and in vitro, and this effect could be mediated at least in part by its direct action on pancreatic acinar cells 1664