Role of Prostaglandins,β-Adrenoceptors,and the Central Nervous System in the Control of Renin Release in Conscious Sodium-Depleted Rats

Abstract

The interrelationship of prostaglandins, β-adrenoceptors, and the central nervous system in the control of renin release in conscious sodium-depleted rats was investigated by acute pharmacologic blockade with systemic administration of indomethacin and propranolol and intracerebroventricular injection of clonidine. Indomethacin and propranolol lowered plasma renin activity significantly with respect to control. When both were administered to the same experimental animals, their renin-lowering effect was additive. Intracerebroventricular clonidine and intraperitoneal propranolol or the injection of both produced a similar renin-lowering effect on sodium-depleted rats. It is concluded that the central nervous system, through an α-adrenergic pathway peripherally mediated by β-adrenergic receptors, plays an important role in the renin release in the conscious sodium-depleted rat. A prostaglandin-mediated pathway is also involved in the renin response to the sodium-depleted state, acting in parallel to the sympathetic nervous system. Since renin does not return to normal after blockade of both pathways, other mechanisms may also be operative.