Objective To observe the effect of Jisheng injection(JI)in preserving isolated heart of mice.Methods Langendorff' s isolated -perfused mouse heart mod el was established.The isolated hearts were preserved in modified Eu-ro -Collins solution(MECS)and MECS with JI added for 3h,7.5h and8.5h respectively.Cardiac functio n,coronary flow and myocardial water -volume (MWV)were observed after 3h ,7.5h and 8.5h of preservation,heart reactivatio n(HR)rate,coronary flow,MWV and time for HR were also observed.Results After 3h of preservation and 20min,30min or 40min of reperfusion,cardiac function and coronary flow in three M ECS +JI groups and especially in that of large dose were improved as compared with t hose in MECS group;MWV in large -dose and moderate -dose groups was obvi-ously lower than that in MECS group(P