Abstract: Partial ligation of the abdominal aorta of rats was adopted to induce left ventriclehypertrophy(LVH).The effects of m-nifedipine(m-Nif)and nifedipine(Nif)on prevention ofhypertrophy and the possible mechanism were investigated。The wet weights of the left ventricle(WWLV)of the LVH group were increased compared withthose of the sham operated group.After treatment with m-Nif and Nif for 4 wks,the WWLVdecreased by 25% ± 9% and 16%± 9%,respectively.the pressurevolume(P-V)curve of thehypertrophied group was markedly elevated,which means that the myocardial compliance wasdecreased,and the stiffness coefficient of the hypertrophied group was significantly elevated than thatof the sham operated group,but the groups treated with m-Nif or Nif were significantly improved。The characteristics of the left ventricular myocardial DHP binding sites were studied.The resultsshowed that the K_d and the B_max were similar in the m-Nif,Nif and hypertrophied groups,but thetotal number of the DHP receptors(TNR)of the LVH group was markly increased than that of thesham operated group,but the TNR of the m-Nif and Nif groups were the same as that of the shamoperated group。These results suggest that the effects of m-Nif and Nif on preventing cardiac hypertrophy andimproving myocardial compliance may be related to their depressing the TNR of DHP.