title: Hypothalamic alpha- and beta-adrenergic systems regulate both thirst and hunger in the rat.
abstract: Adrenergic and adrenolytic drugs were injected directly into the hypothalamus of the rat brain through permanently implanted cannulas and were found to have reliable effects on water consumption in water-satiated and water-deprived subjects. The beta-adrenergic agonist stimulated thirst, and the beta-adrenergic blocker suppressed thirst. Conversely, the alpha-adrenergic agonist suppressed thirst, and the alpha-adrenergic blocker enhanced thirst. These results demonstrate the existence of a hypothalamic beta-adrenergic "thirst" system which opposes a hypothalamic alpha-adrenergic "water-satiety" system. In view of our earlier results demonstrating the existence in the hypothalamus of an alpha-adrenergic "hunger" system which opposes a beta-adrenergic "food-satiety" system, we suggest that a reciprocal inhibitory relationship between these adrenergic hunger- and thirst-regulating systems provides a neurochemical explanation for the ability of organisms to maintain food and water consumption at a constant ratio. In the regulation of both hunger and thirst, the central cholinergic system mimics the hypothalamic beta-adrenergic system and opposes the hypothalamic alpha-adrenergic system.
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage; D000818:Animals
chemical_list: D000316:Adrenergic alpha-Agonists; D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists