Presence of non-cholinergic motor transmission in human isolated bladder

Atropine-sensitivity of the motor transmission in the isolated detrusor preparation from human bladder has been examined. The preparations were contracted by electrical field stimulation consisting either of short trains of pulses or of long trains of pulses. Part of the stable response to short-train stimuli (28%) was resistant to atropine, was not potentiated by physostigmine and was blocked by tetrodotoxin. The stable responses to long-train stimuli were fully blocked by atropine. It is concluded that the detrusor of the bladder in man, in common with other mammalian species, contains a noncholinergic component in its motor transmission, and that prolonged stimulation with long-train stimuli causes an extinction of the non-cholinergic motor transmission, probably through depletion of transmitter stores in the nerve-terminals.