Abstract
The relation between plasma prolactin (PRL) and Na metabolism was studied in adult male rats. During the experiments attention was given to the avoidance of stress. Cannulated rats were infused with 2.5 ml 5% NaCl over a 40 min period. Plasma PRL did not change during or up to 2 h after this infusion. Other rats were subjected to a Na deficient diet for 3 wk. This treatment which induced a marked rise in plasma aldosterone, did not cause a change in plasma PRL. PRL does not have an important role in the regulation of Na balance.