Transmission of Excitation from the Parasympathetic Nerve to the Smooth Muscle

Abstract

TRANSMISSION of excitation from the parasympathetic (cholinergic) nerves to the smooth muscle has been investigated on the colon of the rabbit^1,2. Bennett³ has described the excitatory junction potential in response to stimulation of the intramural nerves of the taenia coli of the guinea-pig. There is, however, much less information about parasympathetic neuromuscular transmission than there is about transmission from sympathetic nerve to smooth muscle^4,5. This seems to be because there is no suitable parasympathetic nerve–smooth muscle preparation like the hypogastric nerve–vas deferens of the guinea-pig. Most smooth muscle cells previously used have both excitatory and inhibitory innervation and when stimulated transmurally the excitatory response may be modified by the inhibitory one. A more suitable preparation was therefore very necessary.