Effect of proximal duodenal acidification upon gastric secretion in the Shay rat

Influence of the proximal small intestine on the gastric hypersecretion in pylorus-ligated rats

The mechanism of the gastric secretory inhibition caused by the simultaneous ligation of the upper and lower duodenum or the jejunum in pylorus-ligated rats was studied. The data obtained from the experiments on surgical manipulation of the small intestine indicated that the absorption of certain substances appeared to be important in maintaining gastric secretion of pylorus-ligated rats. The participation of biliary secretion was negligible, while the ligation procedure per se, which results in the accumulation of duodenal contents, might be partly involved in the mechanism of acid secretion. Pharmacological techniques suggested that the inhibition appeared to be independent of cholinergic nervous reflex and hormonal influence, which is assumed to be released by intestinal acidification.

Inhibitory and stimulatory effects of secretin on gastric secretion in conscious rats

1. The effect of pure secretin on gastrin-induced secretion has been studied in conscious rats with Pavlov or Heidenhain pouches.2. Rapid intravenous injection of secretin did not inhibit a plateau secretion of acid in the Heidenhain pouch, but infusion of the same amount of secretin over two hours inhibited secretion in both Heidenhain and Pavlov pouches.3. A rapid intravenous injection of secretin before the onset of gastrin infusion enhanced the acid secretory response to gastrin in both types of pouches.4. Secretin stimulated pepsin secretion.