Objective:To explore the effect of Valsartan on heart function and a-ctivity of myocardial sarcoplasmic reticulum Ca2+-ATPase in junior rat with heart failure(HF).Methods:The animal model of congestive heart failure was established byfis-tulation of abdominal aorta and inferior vena cava.Rats were randomly divided into 2 groups after 8 weeks of operation:rats without treatment as control group(n=20)

rats treated with Valsartan as valsartan group(n=15).Sham-operated was taken as normal control group(n=15).Valsartan was adminis-tered through direct gastric gavage.The high frequency ultrasound was per-formed 4 weeks after treatment.Myocardial SR was fractionated with velocity centrifugation.Enzyme activity of SERCA2a in SR was detected with ultraviolet spectrophotometre(U V).The time course of Ca2+ uptake was determined by fluorescent spectropho-tometry.Results:Compared with the sham-operated group

left ventricular internal dimension diastole(LVIDd)

left ventricularin-ternal dimension systole(LVIDs)

left ventricular end-diastolic volume(LVEDV)

and left ventricular end-systolic volume(LVESV)were all significantly increased(P<0.01)

while left ventricular ejection fraction(LVEF)

and left ventricular fractional shortening(LVFS)were decreased(P<0.01)in control group.LVIDd

LVIDs

LVEDV

LVESV were all prominently decresed(P<0.01)

while LVEF

and LVFS were inreased(P<0.01)in Valsartan group when compared with control group.Enzyme activity of SERCA2a decreased in control group as compared with other two groups.After adding ATP to the buffer including SR of three groups

Ca2+ uptake was significantly decreased(P<0.01)in control group

and it increased almost to normal level in Valsartan group.Conclusion:Heart function and the enzyme activity of SERCA2a decreased in junior rat with heart failure

Val-sartan can anastate the uptake of Ca2+ by increasing enzyme activity of SERCA2a

and improve cardiac contractility and finally heart function in junior rat with heart failure.