大鼠供心保存期间心肌细胞凋亡的动态变化及褪黑素的保护作用

Dynamic changes of rat donor mycardial cell apoptosis during hypothermic preserv ation and the protective effect of melatonin

目的 探讨大鼠供心保存期间心肌细胞凋亡的动态变化及褪黑素的保护作用。方法 将 80只Wistar大鼠随机平均分为实验组和对照组。实验组在 4℃StThomas液中加入褪黑素(0 .1mmol/L)保存大鼠心脏 ;对照组单用StThomas液保存。分别于保存 4、8、12、2 4、3 6h后 ,各取出8只供心 ,TUNEL法染色检测细胞凋亡情况。以心肌凋亡阳性细胞数占总心肌细胞数的百分比作为心肌细胞凋亡指数。结果 随着保存时间的延长 ,凋亡的心肌细胞数量明显增加 ,各时间点比较 ,差异有显著性 (P <0 .0 1) ;实验组各时间点心肌细胞凋亡指数明显小于相应对照组 (7.68%± 1.0 4%vs 2 4.3 7%± 1.2 3 % ,P <0 .0 1;8.2 7%± 1.17%vs 3 5.73 %± 1.98% ,P <0 .0 1;10 .14 %±1.2 2 %vs 42 .85%± 2 .3 6% ,P <0 .0 1;12 .3 1%± 1.54%vs 58.3 7%± 3 .12 % ,P <0 .0 1;14 .53 %± 1.89%vs 79.65%± 4.16% ,P <0 .0 1)。结论 心肌细胞凋亡程度与供心保存时间呈正比例关系。

ObjectiveTo study the dynamic changes of rat donor myocardial cell apoptosis during hypot hermic preservation and the effect of melatonin.MethodsEighty rats were randomly divided into two groups: experimental group with the i solated rat hearts being preserved in 4?℃ St Thomas solution with melatonin ( 0.1?mmol/L ); control group with the isolated rat hearts being preserved in 4?℃ St Thomas solution only. After preservation for 4, 8, 12, 24 and 36?h, a poptotic index was evaluated by the percentage of mycardial cells using TUNEL po sitive staining.ResultsWith the hypothermic preservation time prolonging, more myocardial cell apoptosi s was found (control group, P< 0.01 ). Apoptotic indexes of mycardial cel l in the experimental group were significantly less than those of the control gr oup ( 7.68?% ± 1.04?% vs 24.37?% ± 1.23?% , P< 0.01 ; 8.27?% ± 1.17?% vs 35.73?% ± 1.98?% , P< 0.01 ; 10.14? % ± 1.22?% vs 42.85?% ± 2.36?% , P< 0.01 ; 12.31?% ± 1.54?% vs 58.37?% ± 3.12?% , P< 0 01 ; 14.53?% ± 1.89 ?% vs 79.65?% ± 4.16?% , P< 0.01 ).ConclusionsThe myocardial cell apoptosis was directly co r related with the hypothermic preservation time. Melatonin ( 0.1?mmol/L ) supp lement in 4?℃ St Thomas solution could significantly reduce donor myocardial c ell apoptosis.