Effects of valsartan alone or in combination with benazepril on blood pressure and left ventricular hypertrophy in spontaneously hypertensive rats

AIM:To evaluate the effects of different doses of valsartan alone or with concomitant be-nazepril on blood pressure,left ventricular hypertrophy,RAASfunction and endoxi nlevel in spontaneously hy-pertensive rats(SHR).METHODS:Thirty SHR(fourteen-week-old,male)were divi ded into five groups(six rats in each group):SHR control group:fed with normal saline;benazepril group:fed with 1 mg·kg^-1·d^-1benazepril);low dose valsartan group:fed with 8 mg·kg^-1·d^-1valsartan;high dose valsartan group:fed with 24 mg·kg^-1·d^-1valsartan;combination drug therapy group:fed with valsartan(8 mg·kg^-1·d^-1)and benazepril(1 mg·kg^-1·d^-1),all for 8 weeks.WKY control group(n=6):fed with normal saline for 8 weeks.RESULTS:SBP,LVM/BW,TDMof SHR were remarkably lower than those of control after drug i n-tervene,and effect on SBP was most remarkable in high dose valsartan group and i nthe combi nation drug ther-apy group;effect on LVM/BW,TDM were most remarkable in combination drug therapy group.Renin activi-ties in plasma and myocardiumwere remarkably i ncreased in drug i ntervene groups.The levels of AngⅡi nplasma and myocardiumwere remarkably increased in two different dose of valsartan treati ng group,and thelarger dose of valsartan were,the higher levels of AngⅡin plasma and myocardium were;decreased in be-nazepril treati ng group and combination drug therapy group.Na⁺-K⁺-ATPase activities in myocardi umwere remarkably i ncreased and the level of endoxi n i n myocardium were remarkably decreased as SBP de-creased after drug intervene.CONCLUSION:Different dose of valsartan alone or combi ned with benazeprilcan decrease SBP of SHR,have the effect of inhibiti ng progression of ventricular hypertrophy.The effect ofcombination drug therapy group was most remarkable among five groups and can avoi d the si de effect of highAngⅡin plasma and myocardiumduri ng long-termuse of valsartan alone.