The Effect of Injections of Hypertonic NaCl‐Solutions into Different Parts of the Hypothalamus of Goats.

Summary. In goats intrahypothalamic injections of hypertonic NaCl‐solutions, within a region medially in the vicinity of the third ventricle, induced drinking of the animals. The most obvious effect was obtained in experiments, where the injection was performed in the middle hypothalamic region near to the para‐ventricular nucleus. Injections of iso‐ or hypotonic solutions had not this effect. Injections of hypertonic NaCl‐solution in the lateral parts of the hypothalamus and in the vicinity of the optic chiasm did not induce any drinking. In seven experiments an obviously increased diuresis together with a diminished concentration of the urine was observed 2–4 hours after the experiments had started. This polyuria was not in every case the consequence of an increased intake of water.