1. [Na+/H+ exchangers, alpha-2-adrenergic receptors, sodium sensitivity and arterial hypertension].
- Author
-
Cloix JF, Le Jossec M, Baud O, Pecquery R, Giudicelli Y, and Dausse JP
- Subjects
- Animals, Drug Resistance, Hypertension etiology, Ion Transport, Rats, Rats, Inbred Strains, Sodium, Dietary adverse effects, Hydrogen metabolism, Hypertension metabolism, Receptors, Adrenergic, alpha metabolism, Sodium metabolism, Sodium, Dietary pharmacology
- Abstract
Existing evidences indicate that a crossed regulation between alpha 2-adrenergic receptors and Na+/H+ exchanger(s) exists, that Na decreases the affinity of alpha 2-adrenergic receptors for agonists and antagonists, that intracellular Na+ and H+ ion concentrations regulate Na+/H+ exchanger activity, that intracellular pH controls the affinity of the alpha 2-adrenergic receptors for their agonists and antagonists. Alterations of alpha 2-adrenergic receptor densities and allosteric regulation by sodium have been demonstrated in sodium-dependent hypertension in rats. Increased Na+/H+ exchanger activity has been reported in genetic hypertension. Nevertheless, cosegregation experiments and human genetic polymorphism suggest that the exchanger could not be related to hypertension. We propose the following hypothesis: the increased Na+/H+ exchanger characteristic of hypertension could be secondary to the abnormalities of the alpha 2-adrenergic receptors found in hypertension, probably through the alteration of the sodium allosteric effect on these receptors.
- Published
- 1992