ENHANCED ACTIVATION OF THE MINERALOCORTICOID RECEPTOR IN GENETICALLY HYPERTENSIVE RATS

The relative abundance and availability of the mineralocorticoid recep tor (MCR) appeared to be similar in the heart, kidney and ocular tissu es of the genetically hypertensive SHR and normotensive WKY rats by a number of criteria including Western blotting, immunoprecipitation, do t blot analysis, and immunohistochemistry, On the other hand, the acti vation of the MCR, as judged by binding to DNA cellulose, was signific antly enhanced in the hearts and kidneys of 14 week-old, hypertensive, SHR rats compared to the normotensive WKY animals, The activation of the renal MCR was elevated in the SHR strain even at the age of six we eks when the tail arterial pressure was statistically identical to tha t of the WKY strain. Thus, precocious receptor activation may represen t a primary lesion leading to hypertension in the SHR strain, thereby providing a new model to elucidate the hypertensive state. (C) 1998 Ac ademic Press.