Responses of the isolated sympathetic nerveductus deferens preparation of the guinea-pig.

An isolated ductus deferens preparation together with the sympathetic hypogastric nerve of the guinea-pig is described. While the preparation showed no spontaneous contractions, nerve stimulation produced longitudinal contractions. The responses to successive periods of nerve stimulation remained constant for several hours. After noradrenaline had been added to the bath fluid for 30 min and then the fluid repeatedly changed to wash out the noradrenaline, the effect of nerve stimulation was greatly increased but declined in the course of 1 hr to the original height. Cocaine also increased the response to stimulation. Preparations made from guinea-pigs which had previously received reserpine responded to nerve stimulation with progressively diminishing contractions. In these circumstances, the administration of noradrenaline restored the response to nerve stimulation to that seen originally.