Hepatic parasympathetic neural effect on glucose balance in the intact liver

Sympathetic nerves to the intact liver of the cat were selectively destroyed by injection of 6-hydroxydopamine into the portal vein 1 week prior to the experiment. Glucose output was calculated from the product of the arterial-venous glucose difference and hepatic blood flow. Hepatic blood flow was monitored by an electromagnetic flowmeter using a hepatic venous long-circuit. Stimulation of the parasympathetic nerves isolated from around the common hepatic artery produced a rapid reduction in hepatic glucose output to one-quarter of control levels by 2 min and to zero by 10 min of nerve stimulation. The data show that hepatic glucose balance is readily influenced by the hepatic parasympathetic nerves.