Effect of electrical stimulation of paraventricular nucleus on stress gastric mucosal lesion in rats

The effect of electrical stimulation of hypothalamic paraventricular nucleus(PVN) on gastric mucosal lesion induced by RWIS (restraint + water-immersionstress) in rats was investigated. The main results were as follows: (1) Electricalstimulation of the PVN could obviously increase the stress gastric mucosal lesion.(2) Microinjection of L-glutamate into PVN could produce similar effect to that ofPVN stimulation. (3) PVN lesion could significantly decrease the stress gastricmucosal lesion. (4) The above mentioned effects were attenuated by vagotomyor atropine injected subcutaneusly. (5) A further study indicated that the gastricmucosal blood flow was reduced upon PVN stimulation, but no obvious changesof gastric juice volume, total acid output, pepsin activity and gastric barrier mucuswere observed. The results mentioned above indicate that the PVN is one of the specific CNSareas capable of increasing the stress-induced gastric mucosal lesion mediatedthrough the cholinergic fibers of the vagal nerve and related to decreased gastricmucosal blood flow, while gastric acid output, pepsin activity and gastric barriermucus do not seem to play any important role.