Objective: To study the effect of Buzhong Yiqi Tang(tonifying middle-Jiao and Qi treatment) on myocardial apoptosis and expression of proteins Fas

FasL and Caspase-3 in hypothyroid rats. Method: The rat of hypothyroidism models were prepared by Kolaja method.Healthy wistar rats were randomly divided into normal control group

model group

Buzhong Yiqi Tang group

Letrox(L-T4)group. The morphological and ultrastructural changes were observed under optical microscope and electronic microscope respectively. Apoptotic cells were measured by TdT-mediated dUTP nick end labeling (TUNEL) method.The expression of apoptosis-related proteins Fas

FasL and Caspase-3 were detected with immunohistochemical methods. TSH was measured by ELISA

Totel 3 Triodothy ronine(TT3)and Totel 4 Triodothy ronine (TT4) were measured by RIA;detect the iodine in urine. Result: Compared with control group

the apoptosis index and the expression of Fas

FasL and Caspase-3 reached the highest level in the model group

myocardial cell injured severely. After treatment the apoptosis index of Buzhong Yiqi Tang group(12.10±0.73) and L-T4 group(29.26±2.10) decreased

the expression of Fas

FasL and Caspase-3 also reduced

and the effectiveness of Buzhong Yiqi Tang group was better(P<0.05). Conclusion: Hypothyroidism causes increase of myocardial cell apoptosis

heightened expression of Fas

FasL and Caspase-3

while Buzhong Yiqi Tang might decrease the myocardial apoptosis and lower the expression of protein Fas

FasL and Caspase-3 significantly

it indicated that Buzhong Yiqi Tang has protective action on myocardial injury of hypothyroidism.