This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Parini, A. Articles by Bianchi, G. Search for Related Content PubMed PubMed Citation Articles by Parini, A. Articles by Bianchi, G.

Hypertension, Vol 10, 505-511, Copyright © 1987 by American Heart Association

ARTICLES

Selective modification of renal alpha 2-adrenergic receptors in Milan hypertensive rat strain

A Parini, L Diop, P Ferrari, GP Bondiolotti, JP Dausse and G Bianchi
Institut National de la Sante et de la Recherche Medicale (U7), Department of Pharmacology, Hopital Necker, Paris, France.

Cerebral and renal alpha-adrenergic receptors play an important role in the control of blood pressure. We studied alpha-adrenergic receptors in the cerebral and renal cortex of Milan hypertensive strain (MHS) and normotensive strain (MNS) rats, a genetic model of spontaneous hypertension linked to a kidney abnormality. Binding of the selective alpha 1-adrenergic antagonist [3H]prazosin and the alpha 2-adrenergic antagonist [3H]rauwolscine was used for receptor studies in tissues of prehypertensive (24-day-old) and hypertensive (60-day-old) rats. In the cerebral cortex, no between-strain differences in alpha 1-adrenergic and alpha 2-adrenergic receptor density and affinity were observed in prehypertensive and hypertensive periods. The density of these receptors increased similarly with age in MHS and MNS rats. In the renal cortex, the differences between MHS and MNS rats concerned alpha 2-adrenergic receptors only. Compared with their age-matched normotensive controls, MHS rats showed 1) a lower affinity for the antagonist (p less than 0.05) in the prehypertensive period, 2) absence of the normal age-related increase in receptor density, and 3) a lower density of [3H]rauwolscine binding sites (p less than 0.001) in the hypertensive period. In this period, studies of competitive inhibition of [3H]rauwolscine binding showed that l-epinephrine bound to one class of sites in MHS rats (pseudo-Hill plot, 0.90) and to two classes in MNS rats (pseudo-Hill plot, 0.68). In addition, the lack of any guanylylimidodiphosphate effect on the l-epinephrine competition curve observed in MHS rats suggests the uncoupling of these receptors from the guanosine 5'-triphosphate binding protein.(ABSTRACT TRUNCATED AT 250 WORDS)

This article has been cited by other articles:

				M. Khalid, N. Ilhami, Y. Giudicelli, and J.-P. Dausse Testosterone Dependence of Salt-Induced Hypertension in Sabra Rats and Role of Renal alpha 2-Adrenoceptor Subtypes J. Pharmacol. Exp. Ther., January 1, 2002; 300(1): 43 - 49. [Abstract] [Full Text] [PDF]

				M. Khalid, Y. Giudicelli, and J.-P. Dausse An Up-Regulation of Renal alpha 2A-Adrenoceptors Is Associated with Resistance to Salt-Induced Hypertension in Sabra Rats J. Pharmacol. Exp. Ther., December 1, 2001; 299(3): 928 - 933. [Abstract] [Full Text] [PDF]