ANGIOTENSIN RECEPTORS IN CARDIAC AND RENAL HYPERTROPHY IN RATS

Angiotensin II mediates its effects through activation of specific ang iotensin (AT) receptors which can be regulated during cardiovascular d isease. This study has investigated whether an increased cardiac and r enal AT receptor density is important in the development of left ventr icular and renal hypertrophy in three rat models of hypertension [spon taneous hypertensive (SHR), deoxycorticosterone acetate (DOCA)-salt an d 2K1C renal hypertensive rats]. Although all hypertensive rats develo ped left ventricular and renal hypertrophy, AT receptor density increa sed only in the left ventricle and kidney of SHR during the developmen t of hypertension. Thus, cardiac and renal hypertrophy per se do not i ncrease AT receptor density. AT receptors were increased in the liver of DOCA-salt rats, 2K1C rats and 52-week-old SHR and in adrenal glands of DOCA-salt rats and SHR. A plausible explanation for tissue-depende nt AT receptor regulation involves tissue-selective control of local r enin-angiotensin systems independent of circulating hormone levels, co mbined with disease-induced cell damage. (C) 1997 Academic Press Limit ed.