Dual Action of Palytoxin in the Isolated Hypogastriic Nerve-Vas Deferens Preparation of Guinea-Pigs

摘要

In the presence of PTX (2 x 10~(-9)M) nerve stimulation of the guinea-pig hypogastric nerve-vas deferens induced a second slower contraction following a first contraction. A selective application of PTX to the muscle and ganglion chamber produced a second response and an inhibitory effect on nerve stimulation, respectively. The PTX-induced second response of the vas deferens to transmural stimulation was nearly abolished by phentolamine or reserpine. These results suggest that the PTX-induced second response is mediated through a noradrenaline release from adrenergic nerve endings and that the inhibitory response by PTX is mainly due to inhibition of ganglion transmission.