Responsiveness of glycogen breakdown to cyclic AMP in perfused liver from rats with insulin-induced hypoglycemia

Brazilian Journal of Medical and Biological Research

M. Vardanega-peicher²  R. Curi¹  S. Pagliarini E Silva²  K.f. Nascimento²  R.b. Bazotte² 

[1] ,Universidade Estadual de Maringá Departamento de Farmácia e Farmacologia Maringá PR ,Brasil

关键词: Insulin-induced hypoglycemia;    Cyclic AMP;    Glycogen breakdown;    Liver metabolism;   

DOI  :  10.1590/S0100-879X2003000100007

来源: SciELO

【 摘 要 】

The responsiveness of glycogen breakdown to cAMP was investigated in isolated perfused liver from male Wistar fed rats (200-220 g) with insulin-induced hypoglycemia. The activation of glycogenolysis by 3 µM cAMP was decreased (P<0.05) in livers from rats with hypoglycemia induced by the administration of insulin or during the direct infusion of insulin into the isolated liver. The direct effect of insulin on glycogen catabolism promoted by 3 µM cAMP occurred as early as 3 min after starting insulin infusion. In contrast, the cAMP agonists resistant to phosphodiesterases, 8Br-cAMP and 6MB-cAMP, used at the same concentration as cAMP, i.e., 3 µM, did not modify the effect of insulin. The data suggest that the decreased hepatic responsiveness of glycogen breakdown during insulin-induced hypoglycemia is a direct effect of insulin decreasing the intracellular levels of cAMP.

【 授权许可】

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