Effect of restraint and footshock stress and norepinephrine treatment on gastric emptying in rats

Abstract

We investigated the effects of restraint and footshock stress and norepinephrine treatment on gastric emptying. The gastric emptying was significantly inhibited by restraint stress. β3-adrenergic antagonist canceled the inhibition of gastric emptying caused by restraint stress, while β1-, β2-, α1-, and α2-adrenergic antagonists did not affect the inhibition. Norepinephrine treatment also inhibited gastric emptying. The inhibition by norepinephrine treatment was canceled by β1-, β2-, and β3-adrenergic antagonists, but not by α1- and α2-adrenergic antagonists. On the other hand, footshock stress did not affect gastric emptying. These results suggest that β3-adrenoceptors play an important role in the inhibition of gastric emptying caused by restraint stress, while nonspecific β-adrenoceptors are involved in that caused by norepinephrine treatment.