The location of the chemoreceptor controlling gastric acid secretion during hypoglycaemia.

1. The injection of 2-deoxy-D-glucose directly into the lateral hypothalamic area of rats, but not elsewhere, caused a prompt and sustained secretion of acid by the stomach at a rate comparable to that due to insulin hypoglycaemia.2. Acid secretion provoked by such injections, like that resulting from hypoglycaemia, could be stopped by raising the plasma glucose concentration by the intravenous infusion of glucose.3. Unilateral intrahypothalamic injection of 2-deoxy-D-glucose activated both vagi for, although cutting one vagus reduced the secretion, division of both was necessary to abolish it.4. Gastric acid secretion evoked by a systemic stimulus (insulin-induced hypoglycaemia or intravenous 3-O-methylglucose) could be prevented by inactivating the lateral hypothalamic area on each side with phenol or lignocaine.5. It is concluded that there exists in the lateral hypothalamic area a chemoreceptor, responsive to a lack of metabolizable glucose, which can initiate and sustain the vagally mediated secretion of acid by the stomach.