Differential effect of glutathione depletion on glycogenolysis in isolated rat hepatocytes mediated by alpha-adrenoceptor agonists and glucagon

Glutathione (GSH) exerts a variety of cytoprotecive effects, but is readily depleted from cells under a variety of stressful stimuli. The impact of GSH depletion on receptor-mediated activity in rat hepatocytes has been studied with regard to glycogenolysis stimulated with a-adrenoceptor agonists or glucagon, which exert their actions through different signalling pathways. Depletion of GSH content (70%) by diethyl maleate had no effect on the redox status of the cells or on basal or glucagon-stimulated glycogenolysis, but significantly reduced the response to the a-adrenoceptor agonists adrenalin and phenylephrine. These results highlight the possible modulatory effects of GSH on receptor-mediated activity in hepatocytes.

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