“…The sensitivity of the uterus to these agonists is found to vary with the changing endocrine conditions during the oestrous cycle, being most sensitive during prooestrus and early oestrus. It has been proposed that this change in sensitivity might be the result of variations in the density of beta-adrenoreceptors in the myometrium during the oestrous cycle (Korenman & Krall, 1977). Using an autoradiographic technique we have studied the distribution of /I-adrenoreceptors in the rat uterus during the oestrous cycle.…”