Preoperative sodium appetite experience and hypothalamic lesions in rats

When a sodium deficit is induced in rats without lesions, they increase their saline intake regardless of prior experience. By contrast, this experiment found that rats with lateral hypothalamic lesions increased their saline intake only when they had had preoperative experience ingesting saline in response to a sodium deficit. Rats were given natriuretic and mineralocorticoid treatments to induce sodium appetite. The role of preoperative experience in neural function are discussed.