Acid Inhibition by the Gastric Antrum

Abstract

A study of acid inhibition by the gastric antrum in 27 dogs with either vagally innervated, or denervated fundic pouches. Antrum innervation was studied in its relation to humoral and/or reflex changes by comparing the results found before and after vagal denervation with those of acid or cocaine irrigation. After exclusion of the vagally innervated antrum in Heidenhain and Pavlov pouch animals, the 24-hour acid output and the response to a test meal and histamine were not significantly changed. The response to insulin hypoglycemia was increased. After exclusion in Dragstedt pouch animals, the 24-hour acid output and the response to a test meal and insulin hypoglycemia were increased. The histamine test was un-changed. Irrigation of the innervated excluded antrum with acid did not reduce the response to histamine. Acid markedly reduced the response to a test meal and insulin hypoglycemia. Irrigation with cocaine reduced the response to a test meal and insulin hypoglycemia in a manner not significantly different from acid. The results of denervation and antrectomy of the excluded antrum on the above tests did not consistently differ from those found during acid irrigation of the innervated antrum. The results of the vagally innervated excluded antrum-fundic pouch preparation can best be explained by a loss of a local controlling action of an acid pH on the gastrin mechanism, thus allowing for an increased liberation of vagal gastrin.