Sodium Regulation in the Affinity of Renal α₂-Adrenoceptors for Epinephrine in Sabra Salt-Sensitive and Salt-Resistant Rats

Abstract

Sodium ions markedly decreased in vitro renal α₂-adrenoceptor affinity for epinephrine in Sabra hypertensive (SBH) but not in normotensive (SBN) rats. Under these conditions, affinity of α₁-adrenoceptor for epinephrine was unchanged in SBH and SBN rats. If these data could be confirmed in vivo, the sodium ion, by acting as an inhibitor, could modify the effect of agonists on renal α₂-adrenoceptors in SBH rats. Conversely, the absence of sodium regulation in SBN rats might represent a genetically mediated change responsible for the resistance to the development of salt-induced hypertension. Am J Hypertens 1991;4:267–270

Kidney, α-adrenergic receptors, Sabra rats, sodium, [³H]yohimbine, [³H]prazosin

© American Journal of Hypertension, Inc. 1991