Central Nervous and Pituitary Control of Aldosterone Secretion in the Rat

Abstract

This chapter discusses the role of the central nervous system (CNS) and the pituitary in the control of aldosterone secretion in the rat. Numerous studies exploring possible relationships between the brain and aldosterone secretion are reviewed. In addition to an influence of the subcommissural area in the regulation of aldosterone secretion, evidence has been found indicating an influence of this area on sodium metabolism. Since the hypothalamus exerts control over pituitary secretions, subsequent experiments were designed to study the effects of elimination of this control by hypothalamic lesions on aldosterone secretion in sodium-deficient rats. For example, if it were possible to selectively block the release of growth hormones (STH) by specific lesions in the hypothalamus, the importance of STH for the regulation of aldosterone secretion might then be demonstrated in the absence of other perturbations in pituitary function. In contrast to normal subjects, hypopituitary patients failed to show a significant increase in aldosterone secretion during adrenocorticotropic hormone (ACTH) infusion, although the 17-hydroxycorticosteroid response to ACTH was not impaired.