A note on the electrically transmurally stimulated isolated trachea of the guinea-pig

Abstract

The isolated trachea of the guinea-pig was stimulated electrically transmurally to give a biphasic response. The initial contraction was abolished by atropine and was rapidly succeeded by relaxation which was blocked by low concentrations of dichloro-isoprenaline. The relaxation was also blocked by procaine, guanethidine, or by previous treatment of the animal with reserpine, but not with hexamethonium. It was concluded that the effects of transmural stimulation were mediated by post-ganglionic adrenergic nerves innervating beta receptors.