[Cardiotropic effects of luliberin. Interaction with rat heart sarcolemmal membrane]

Studies of the effects of luliberin (luteinizing hormone-releasing hormone) on cardiac cells showed that the hormone is specifically bound by the sarcolemmal membrane. The activity of the membrane enzyme -- reception of luliberin involves two types of binding sites with high (K' = 10(7) M-1) and low (K'' = 10(5) M-1) affinities for the hormone, respectively. The hormone has no effect on the activities of adenylate cyclase and phosphodiesterase.