OBJECTIVETo study the effects of different doses of taurine (Tau) on calcium ion concentration ([Ca2+]i) and ATPase on cardiocyte membrane of diastole heart failure rats.

METHODDiastole heart failure model was established by the coarctation of abdominal aorta. Four weeks after operation, forty diastole heart failure rats were divided into four groups randomly as follows, model (normal saline 2 mL), taurine (400 mg x kg(-1) x d(-1)), taurine (200 mg x kg(-1) x d(-1)), taurine (100 mgx kg(-1) x d(-1)), with 10 rats for each group (n=10), and 10 sham operation rats was taken as control(normal saline, 2 mL). After 4 weeks administration, Isolate single cardiocyte by enzymatic isolation method which were loaded with Ca2+-sensitive fluorescent indicator Fluo-3/AM. [Ca2+]i was measured by laser scanning confocal microscope [LSCM], and represented it by fluorescent intensity [FI]; ATPase activity of cell membrane was measured by the method of enzymatic reaction chromatometry.

RESULTCompared with the control group, [Ca2+]i in cardiocyte increased markedly and the ATPase activity of cardiocyte membrane decreased significantly in the model group. Compared with the model group, fluorescent value decreased and ATPase activity increased significantly in Tau high-dose group; fluorescence value and ATPase activity decreased significantly in Tau mid-dose group; fluorescent value decreased and ATPase activity increased significantly in Tau low-dose group.

CONCLUSIONLarge dosage of Tau can increase ATPase activity on cardiocyte membrane, improve [Ca2+]i in cardiocyte and antagonise calcium overload of DHF rats.