[A kinetic analysis of the alpha 1-adrenergic reaction of the smooth muscles in the rat vas deferens].

The kinetics of alpha 1-adrenergic response to noradrenaline was studied in isolated epididymal section of the rat vas deferens. Two discrete pools of alpha 1-adrenoreceptors differing by their affinity to noradrenaline, were revealed. The alpha 1-adrenoreceptors also differed from each other in their ability to interact with one or two molecules of the transmitter. Functional role of heterogeneity of the receptors is discussed.