Reaction of the Gall Bladder to Stimulation of Visceral Nerves

Abstract

In a recent article 1 evidence was presented to show that both human and animal gall bladders are subject to the control of reflexes originating in the gastro-intestinal tract; that in unanesthetized cats faradic stimulation of the pars pylorica of the empty stomach induces contraction of that organ and reflex emptying of the gall bladder; and that faradic stimulation of any part of the alimentary tube from stomach to caecum will inhibit the contraction of a gall bladder that is emptying after a meal of egg-yolk.

Since then, employing similar methods (i. e., sewing insulated electrodes to various internal surfaces) these observations have been extended to the colon and rectum of the cat (3 animals), and to the peritoneal surface of the abdominal musculature (1 animal), thereby showing that faradic stimulation of certain parts of the gut-tract or body-wall that are supplied by sacral and thoracic nerves, respectively, also induces inhibition of the emptying gall bladder.

Using a modification of this method, by means of which electrodes may be wrapped around nerve trunks and insulated from surrounding parts, it has been found possible to stimulate the nerves of the unanesthetized animal after its recovery from the operation and thereby to induce changes in the tonus of the gall bladder as revealed by X-rays of its roentgen-opaque contents. Preliminary attempts to ascertain the nerves involved in these reflex pathways have demonstrated that direct stimulation of the plexus that accompanies the left gastric artery (2 animals), or of the hepatic plexus (1 animal), induces relaxation of the contracted gall bladder.

This preliminary report is based on 14 experimental animals. In the 8 animals in which the conditions prerequisite to inhibition were established (i. e., emptying of the gall bladder following ingestion of egg-yolk), faradic stimulation sufficient to cause slight pain, repeatedly and consistently stopped the flow of cystic bile.