EFFECTS OF DIMETHYLPHENOXY)-2-(3,4-DIMETHOXYPHENYLETHYLAMINO) PROPANEHYDROCHLORIDE ON HEART FUNCTION, LACTATE-DEHYDROGENASE AND ITS ISOENZYMES IN RATS WITH CARDIAC-HYPERTROPHY

AIM: To investigate the effects of dimethylphenoxy)-2-(3,4-dimethoxyph enylethylamino) propane hydrochloride (DDPH) on cardiac systolic and d iastolic function, lactate dehydrogenase (LDH) activity, and LDH isoen zymes in rats with cardiac hypertrophy. METHODS: The cardiac hypertrop hy of rats was induced by partly occluding abdominal aorta. The rats w ere given ig DDPH for 8 wk 4 wk after operation, and isolated working heart was made. RESULTS: Eight wk later, in model group, left ventricl e systolic pressure (LVSP), LV + dp/dt(max), - dp/dt(max) and aorta pr essure (AP) decreased by 20.2 %, 20.0 %, 41.4 %, and 13.6 %, respectiv ely. Left ventricle ending diastolic pressure (LVEDP) increased by 173 .9 %. The hemodynamic study showed that flowing liquid of aorta (AF) a nd coronary (CF) and cardiac output (CO) decreased by 49.4 %, 41.2 %, and 48.9 %, respectively. After the rats were given ig DDPH, the all a bove-mentioned parameters recovered to different degrees. Under condit ion of cardiac hypertrophy, LDH isoenzymes and subunits changed signif icantly. Isoenzymes LDH3, LDH4, and LDH5, especially LDH5 increased, L DH1 decreased, subunit M in hypertrophied heart increased; 1.69 times than that in nomal heart. DDPH could decrease subunit M and increase s ubunit H. CONCLUSION: DDPH can increase cardiac function, coronary now and reverse changes of LDH isoenzymes in rats with cardiac hypertroph y.