[The membranotropic action of corticosterone on the contractile activity of the portal vein smooth-muscle cells]

Abstract

In vitro, noradrenaline (NA) added in increasing concentrations induced a phase-tonic response of portal vein, much more obvious in the SHR rats as compared with the WKY ones. When studying the corticosterone (CS) effect (10(-8) M) on the Na-induced contractile activity, hormone's own effect as well as its potentiating vasoconstrictory action were revealed. This, however, only occurred in the WKY rats. The initial effect of corticosterone was absent in the SHR rats. The differences in actions of Na and CS upon the contractile activity of vessels in normo- and hypertensive rats are discussed from the standpoint of the membrane theory of arterial hypertension pathogenesis.