Role of the sympathetic nervous system in peptic ulcer production in rats.

The role of the sympathetic nervous system in gastric acid secretion and in experimental duodenal ulceration (cysteamine induced) was studied in rats. The animals were divided randomly into seven groups: (1) control, (2) sham-operated, (3) surgical sympathectomy, (4) chemical sympathectomy (6-HODA), (5) vagotomy, (6) surgical sympathectomy plus vagotomy, and (7) chemical sympathectomy plus vagotomy. Results on gastric acid secretion were expressed as gastric acid output (GAO = micronEq of acid secretion in 1 hour). The means in the control and sham groups were 447.83 +/- 26.67 GAO and 399 +/- 36.4 GAO, respectively. The means in the sympathectomized rats (surgically = 562 +/- 27.21 GAO and chemically = 648.66 +/- 46.53 GAO) were higher (P less than 0.01) than those of the control and sham groups. In the vagotomized group the mean was 156.6 +/- 17.64 GAO, lower than those of the control and sham groups (P less than 0.001). The incidence of ulceration was 47.5% and 46% in the control and sham groups, respectively. Both the sympathectomized groups (surgically, 73%; chemically, 77%), had a significantly elevated incidence of ulceration as compared with the controls (P less than 0.01). The vagotomized group had a 14% incidence of ulceration. These results clearly indicate that sympathectomy has a definite effect on gastric acid secretion and on the incidence of experimental peptic ulceration in rats.