Adenosine 3',5'-cyclic monophosphate and adrenal tumor cell morphology.

Abstract

Cultured adrenal tumor cells respond to adrenocorticotropin (ACTH), adenosine 3′,5′-cyclic monophosphate (cAMP), cholera enterotoxin (CT), andEscherichia coli enterotoxin with increased steroidogenesis and a reversible alteration of monolayer morphology. The morphological response is not due specifically to the interaction of ACTH or CT with a membrane receptor site, because both cAMP and theophylline, which work intracellularly, also stimulated steroidogenesis and rounding of adrenal cells. The morphological alteration appears to be unrelated to stimulation of steroido-genesis or protein synthesis, inasmuch as CT in the presence of aminoglutethimide or cycloheximide still caused rounding and cAMP accumulation without increased steroid production. These results suggest that increased intracellular cAMP concentration may be related to the observed change of flattened adrenal cells to a spherical shape in monolayer cultures.