Exaggerated Prandial Drinking in the Rat without Salivary Glands

Abstract

RATS eating dry foods drink water when they eat. Teitelbaum and Epstein¹ have called this prandial drinking or drinking at mealtime. Their attention was directed to it by the observation that rats recovered from the initial aphagia and adipsia produced by lateral hypothalamic lesions drink water only when they eat dry food. That is, they are pure prandial drinkers. Unlike the normal rat which will continue to drink water in the absence of food, the rat with lateral hypothalamic lesions that is no longer aphagic or adipsic will not drink water when it cannot eat, and it will drink less, not more, water in response to direct challenges to the regulation of body water that depress feeding, such as water deprivation, increased serum osmotic pressure, and hyperthermia².