Responses of the Denervated Rat Urinary Bladder to Alfa Adrenoceptor Stimulation

Abstract

The contractile responses of the rat detrusor muscle to noradrenaline were increased 2-3 wk after partial denervation but returned to control values 6-9 wk after the denervation, probably because of reinnervation of denervated muscle cells. After partial denervation (6-9 wk) the excitatory .alpha.-adrenoceptor mediated response to stimulation of the remaining intact nerves was predominant. There was a masking of the subsequent inhibitory .beta.-receptor response, which at this time was seen only after .alpha.-receptor blockade. The possibility of an outgrowth of adrenergic fibers activating .alpha.-receptors in muscle cells normally not innervated by adrenergic nerves was discussed.