Mechanism of hypothalamic control of gastric contractions in the rat

Gastric hunger contractions in hypothalamic hyperphagic and aphagic rats are similar to those of normal rats. Heat, cold and epinephrine inhibited hunger contractions in both types of hypothalamic animals. The gastric hunger contractions of aphagic rats are inhibited normally by glucagon. However, doses of glucagon which inhibit hunger contractions in normal rats fail to do so in hyperphagic hypothalamic animals whether obese or reduced to normal weight, in spite of the fact that responses are similar to those seen in normal animals. This ventromedial ‘glucoreceptive’ hypothalamic area thus seems to exert a considerable measure of control upon gastric hunger contractions while the lateral area does not. A scheme integrating hypothalamic, metabolic and gastric factors in hunger is proposed.