E-series prostaglandins activate cAMP-mediated potassium currents in follicle-enclosed xenopus oocyte

Receptor-mediated responses to prostaglandins E₁ and E₂ are shown by electrophysiological methods in follicle-enclosed oocytes of Xenopus laevis. In voltage-clamped oocytes, prostaglandins E₁ and E₂ elicited an outward hyperpolarizing current. This outward membrane current was caused by an increase in K⁺ conductance. The prostaglandin-induced current was augmented by adenylate cyclase activator, forskolin, and by phosphodiesterase inhibitor, theophylline, indicating that adenosine 3′, 5′-cyclic monophosphate (cAMP) is involved in activating the K⁺ current. The prostaglandin responses were either abolished or greatly reduced by removing follicular cells with collagenase, suggesting that prostaglandin receptors reside in the follicular cells.