A new method for the collection of gastric secretion in conscious rats.

Abstract

A new method has been devised for the collection of gastric secretion in conscious rats. A stainless steel wire loop was placed around the pylorus. Seven to 10 days later when the rat had recovered from the operation and was showing significant weight gains and food intake, it was starved for 48 h and collection of gastric juice was begun by tightening the wire loop. This effectively occluded the pylorus, and had the advantage that the animal remained conscious during the procedure. The rat was sacrificed after a certain period of time, and the gastric content was collected. After centrifugation, the total acidity of the supernatant was determined by titration with 0.01 N NaOH. With the present method, the total acid output as well as the rate of gastric secretion were significantly higher than those of similarly operated rats under restraint and those which were investigated using the Shay method. The gastric mucosa of each rat was examined and it was found that the incidence of gastric lesions in the control group using the present method was significantly lower than that in the other operated groups. This method is regarded as less unphysiological than the widely used Shay technique, in which pyloric ligation is performed in the unconscious rat immediately before the collection of gastric juice.