Stomach-brain communication by vagal afferents in response to luminal acid backdiffusion, gastrin, and gastric acid secretion

摘要

Vagal afferents play a role in gut-brain signaling of physiological and pathological stimuli. Here, we investigated how backdiffusion of luminal HC1 or NH_40H and pentagastrin-stimulated acid secretion interact in the communication between rat stomach and brain stem. Rats were pretreated intraperi-toneally with vehicle or appropriate doses of cimetidine, omeprazole, pentagastrin, dexloxiglumide (CCK_1 receptor antagonist), and itriglu-mide (CCK_2 receptor antagonist) before intragastric administration of saline or backdiffusing concentrations of HC1 or NH_40H. Two hours later, neuronal activation in the nucleus of the solitary tract (NTS) and area postrema was visualized by c-Fos immunohistochemistry. Exposure of the rat gastric mucosa to HC1 (0.15-0.5 M) or NH_40H (0.1-0.3 M) led to a concentration-dependent expression of c-Fos in the NTS, which was not related to gender, gastric mucosal injury, or gastropyloric motor alterations.