Niu Hao，Zhao Jinxian，Zhu Bin

    Department of internal medicine，Zhongtang People’s Hospital，Dongguan523220.

    【Abstract】 Objective To investigate the function of cardioplegia in IPC-induced cardioprotection through comparing the effects of ischemic preconditioning(IPC)and IPC followed by cardioplegia on immature rabbit hearts globally suffered ischemia-reperfusion injury.Methods New Zealand rabbits aged14-21days weighing220-280g were used.The animals were anesthetized and heparinized.Chest was opened and heart was quickly removed and aorta was connected to Langendorff within30s after excision.The hearts were perfused with Krebs-Henseleit buffer balanced with gas mixture(O 2 :CO 2 =95%:5%)at60cmH 2 O(perfusion pressure).IPC consisted of5min global isˉchemia plus10min reperfusion.Thirty two immature rabbit hearts were randomly divided into four groups:CONⅠ(n=8)，was only made globally ischemic by withholding perfusion for30min followed by40min reperfusion;IPC(n=8)，IPC and30min noreperfusion followed by40min reperfusion;CONⅡ(n=8)，A cardiac arrest was induced with4℃St ThomasⅡcardioplegic solution and a45min nor eperfusion followed by40min reperfusion;IPC+St.Ⅱ(n=8) ......