Inhibition of gastric secretion by atropine in conscious rats.

1. The effect of atropine on acid and pepsin secretion, stimulated by feeding, vagus excitation or infusions of gastrin, histamine and methacholine, was studied in conscious rats provided with a Pavlov or a Heidenhain pouch.2. The acid and pepsin secretion in response to food was substantially suppressed by atropine in the Pavlov pouch.3. The strong stimulatory effect of 2-deoxy-D-glucose on acid and pepsin secretion in the Pavlov pouch was almost abolished by atropine.4. A plateau secretion of acid obtained by infusion of submaximal doses of hog gastrin II, was significantly inhibited by atropine in the Pavlov and the Heidenhain pouch.5. Methacholine-induced acid and pepsin secretion in the denervated Heidenhain pouch was nearly completely inhibited by atropine.6. A plateau secretion of acid evoked by infusing histamine in a near maximal dosage was inhibited by atropine to the same extent as the gastrin-induced secretion in the Pavlov pouch.7. The mode of action of atropine as a gastric secretory inhibitor is discussed.