Effect of colchicine on micturition reflex in rats.

Intracerebral or intraspinal cord, but not intraperitoneal, injection of low doses of colchicine in rats induces specific toxic symptoms. This paper deals in particular with the effect of colchicine on micturition. After the injection of 5-25 micrograms/rat in cerebral ventricle or 2.5-20 micrograms/rat intraspinal cord, bladder content was markedly increased, due to a dramatic urine retention. Time of latency of vesical retention was related to the dose and to the route of colchicine administration. Cystometrographic analyses were performed in control and treated rats at various intervals of time after the injection: bladder tone, as expressed by the delta P/delta V ratio, monitored from 12 to 120 hr after colchicine injection, decreased more and more during time, suggesting that the observed vesical hypotonicity is an irreversible phenomenon.