EFFECT OF INHIBITION OF GLUCONEOGENESIS ON ARGININE-INDUCED INSULIN-SECRETION

It is well known that several amino acids, such as arginine, are poten t stimuli for insulin and glucagon secretion from the pancreas. Recent ly, vagal arginine sensors, which modulate arginine induced pancreatic hormone secretion, have been reported to exist in the liver. The pres ent investigation was designed to evaluate the role played by gluconeo genesis in this hepatic influence. To this end, we studied the effects of an intraperitoneal injection of 3-mercaptopicolinic acid (3-MPA), a gluconeogenic inhibitor, on the pancreatic hormonal response induced by intraperitoneal administration of arginine (1 g/kg body mass) to h epatic vagotomized and sham vagotomized rats. Fifteen min following th e injection of arginine, the increases in glucose and insulin concentr ations were significantly lower in rats with an inhibited gluconeogene sis than in rats with an intact capacity for gluconeogenesis. There we re no effects of the hepatic vagotomy on the arginine induced hormonal responses either with or without the 3-MPA injection. The results sug gest that gluconeogenesis is implicated in the hepatic modulation of a rginine-induced pancreatic