Hepatic and mesenteric artery resistances after sinoaortic denervation and hemorrhage

Abstract

The effect of sinoaortic denervation on resistances of superior mesenteric, hepatic, and gastroduodenal beds was determined in dogs anesthetized with morphine and chloralose. Mesenteric resistance increased and was 100% above control 15 min. after the denervation. Hepatic artery flow with all branches of the artery intact increased with blood pressure. Gastroduodenal resistance increased 50% above control. In preparations in which blood pressure was stabilized after sinoaortic denervation, resistance in the mesenteric bed increased as it did without stabilization. Hepatic artery resistance with the gastroduodenal artery ligated increased 50% during the 1st min. after denervation but 5 min. after denervation had returned to near control value. Following hemorrhage (3% of body wt) mesenteric resistance increased 130% and hepatic arterial 10%, with gastroduodenal artery ligated. It is concluded that both mesenteric and hepatic beds can be influenced by central neurogenic control. However, the hepatic resistance vessels are influenced to a lesser degree, and can readily escape from control after a relatively short period during which flow is decreased, while the vasoconstrictors maintain a reduction in mesenteric flow for longer periods.