Adrenal Glucose-6-Phosphatase : Alterations in Intracellular Distribution induced by Treatment with Adrenocorticotrophic Hormone

Abstract

HAYNES et al.¹ have proposed a mechanism of the action of adrenocorticotrophic hormone (ACTH) on the adrenal gland in which glucose-6-phosphate (G-6-P) plays a most important part. The increased rate of production of G-6-P, arising from the activation of phosphorylase by ACTH to produce increased quantities of glucose-1-phosphate and the subsequent conversion of the glucose-1-phosphate to G-6-P by phosphoglucomutase, results in an increased metabolism of G-6-P by oxidation to 6-phosphogluconic acid. This oxidation produces reduced triphosphopyridin nucleotide (TPNH) and the TPNH serves as a source of energy for various steps in the production of steroids². However, G-6-P may also be metabolized by dephosphorylation, affected by the enzyme glucose-6-phosphatase (G-6-Ptase).