Cyclic AMP mediation of the hormonal stimulation of 14C-acetate incorporation by Heliothis armigera pheromone glands in vitro

Abstract

Evidence is presented for hormone-controlled adenosine 3',5'-cyclic monophosphate (cAMP)-mediated incorporation of 14C-acetate by in vitro pheromone gland preparations of Heliothis armigera. Basal intracellular cAMP concentrations of in vitro pheromone glands increase 28-fold in the presence of methanolic brain-complex extracts after 5 min of incubation. This intracellular cAMP increase shows a dose-dependent response. Studies on isolated pheromone gland preparations show that 8-bromo-cAMP added to the incubation media stimulates acetate incorporation thereby mimicking the hormonal response. This effect was duplicated by forskolin and isobutyl-methylxanthine. In addition, forskolin exhibits a dose-dependent stimulatory effect on the incorporation of 14C-acetate by such isolated in vitro pheromone glands. High-pressure liquid chromatographic analysis of the radioactive products, extracted by hexane from pheromone glands and media, revealed a stimulation by forskolin of a product exhibiting the same retention time as (Z)-11-hexadecenal, the main pheromone component of H. armigera. In addition, thin-layer chromatographic analysis revealed co-elution with (Z)-11-hexadecenal on stimulation by 8-bromo-cAMP.