Urinary bladder smooth-muscle electrical activity: response to atropine and bethanechol

Fourteen patients with spinal cord injuries and lower motor neuron type neurogenic bladders and 12 patients with upper motor neuron type neurogenic bladders and spinal cord injuries, were evaluated before and after bethanechol or atropine, respectively. They were compared with 5 patients with benign prostatic hypertrophy or bladder tumors but without neurologic disease. Both drugs were found to modify partially smooth-muscle response. The implications of these results are consistent with the production of electrical activity by the smooth-muscle cells of the bladder wall.