Prostanoids and adrenaline release: a study of [3H]adrenaline efflux from the rabbit isolated, perfused, adrenal gland.

[3H]Adrenaline was incorporated in an isolated perfused preparation of the rabbit adrenal gland and the effects of indomethacin, PGE2 and PGI2 on its release were investigated. Efflux of [3H]adrenaline was elicited by electrical stimulation of the splanchnic nerve (60 s at 5 Hz). Indomethacin (3 and 30 microM) had no effect on stimulation-induced efflux. PGE2 (30, 90 and 300 nM) reduced the efflux; with 90 nM PGE2 the inhibition amounted to approximately 30%. PGI2, in concentrations from 90 to 600 nM, was without effect. These findings indicate that release of [3H]adrenaline from the rabbit adrenal gland is not subject to modulation by endogenous adrenal prostaglandins; however, PGE2 may play a role in some pathological situations.