Alterações secretórias de insulina na desnutrição proteica em modelos experimentais.

Abstract

The protein restriction in early stages of life causes several changes in endocrine pancreas, among these alterations are reduction in insulin secretion and changes several enzymes. The mechanisms involved in these changes are not yet completely elucidated, but may be related to changes in signaling pathways that potentiate insulin secretion in presence of glucose. The effects of carbamylcholine (CCh) on insulin secretion were studied in pancreatic islets from rats maintained on a normal (17%; NP) or low (6%; LP) protein diet. Isolated islets were incubated for 1 h in solution containing glucose, with or without charbamylcholine (CCh). The CCh-induced insulin secretion was higher in NP compared to LP islets. Western blotting revealed that the PLCβ1 contents of LP islets were 25% lower than in NP islets (P < 0.05). In conclusion, a reduced expression of PLC1 may be involved in the decreased insulin secretion by islets from LP rats following CCh stimulation. Our results indicated a possible relationship between a low protein diet and a reduction of PLCβ1 expression. These alterations in PLCβ1 may be partly responsible for the decreased insulin secretion by islets from rats fed a low protein diet.