Acid secretory responses to histamine, pentagastrin, and feeding before and after vagal denervation of fundic pouches in cats.

Abstract

Dose-response curves for acid output to histamine, pentagastrin and feeding were determined in cat before and after vagal denervation of the fundic pouch. Before denervation, the maximal response to the three stimulants was equal. Denervation reduced the acid response to histamine by decreasing the secretory capacity, and to pentagastrin by decreasing both the secretory capacity and sensitivity of the oxyntic glands. In this respect the effect of local and truncal vagotomy is equal in cats. The reduction of the response to feeding was greater than to histamine and pentagastrin. In the denervated pouch, the maximal response to feeding amounted to two-thirds of that to histamine and pentagastrin. This demonstrates that feeding does not release enough gastrin to induce maximal rate of acid secretion in the absence of vagal impulses. Nevertheless, feeding and pentagastrin produced equal maximal responses before denervation. This suggests that vagal impulses during feeding produce greater enhancement than basal vagal tone of the acid response to submaximal doses of gastrin.