Sodium appetite in response to sodium deficiency in baboons

Abstract

Naive male baboons exhibit little hedonic intake of 300 mM NaCl but develop a robust Na appetite with Na deficiency. With the first episode of Na deficiency, increased drinking of saline solution occurs in the first 1-3 days, but correction of deficit is slow over 5-6 days. Na intake and repair of deficit become more rapid with experience. After three episodes of Na deficiency, the baboons immediately drink Na solution when given access and repair the deficit over 1-2 days. These experimental data showing an innate Na appetite in primates are important in relation to behavior of gorillas and chimpanzees in the wild and anthropological records of behavior toward salt sources. They open an avenue for physiological analysis of cerebral mechanisms subserving Na appetite in primates and humans.