A Comparison of the Effects of ACTH, Cyclic AMP, Dibutyryl Cyclic AMP, and PGE2on Corticosteroidogenesis in Vitro

Abstract

Corticosterone synthesis increased during prostaglandin E₂ (PGE₂) superfusion of adrenal bisects of acutely hypophysectomized female rats. The initial rate of corticosterone synthesis during PGE₂ and ACTH stimulation were similar, and peak output occurred at 60 min. Cyclic 3′,5′-adenosine monophosphate and its dibutyryl derivative (cAMP and dbcAMP) induced maximal corticosterone formation at 90 and 150 min respectively. The ACTH, cAMP and dbcAMP responses decayed at a comparable slow rate, whereas the response to PGE₂ decayed rapidly, and the shape of the response curve was markedly different from the other compounds. This indicates that the overall corticosteroidogenic response to PGE₂ is different from that of ACTH. This work substantiates the hypothesis that cAMP is at least in part the mediator for ACTH action but demonstrates the need for exercising caution in utilizing dbcAMP as a tool for studying the mechanism of cAMP action. (Endocrinology90: 371, 1972)