The Effects of Stomach Distenion on Thirst

In 1951, Kohn(1) made a comparative study of the immediate effects on hunger drive in albino rats by giving each time (a) 14 cc. enriched milk directly into the stomach, (b) 14 c.c. enriched milk taken normally by mouth, and (c) a control injection of 14 c.c. of isotonic saline. For his measure of hunger, Kohn used the rate of per-forming a response (pushing a little panel) reinforced with food periodically. Response rate immediately after the milk injection was lower than that after the saline injection, and was much still lower than that after milk drunk by mouth. In 1952, Berkun, Kessen and Miller(23) used Kohn's method with a different measure which was the amount of milk drunk during a 10-min. test period from a glass tube, and found the same result as Kohn's. That is, the animals drank less after an injection of milk via fistula than after an injection of isotonic saline, and drank more than after milk drunk by mouth. According to these experimental results, they found stomach distention to be a thirst-drive reduction factor.