缺血再灌注对在体兔窦房结细胞凋亡影响的研究

Influence of Ischemia-Reperfusion on Apoptosis of Sinoatrial Node Cells in Rabbits In Vivo.

探讨缺血再灌注对在体兔窦房结细胞凋亡的影响。取家兔 90只随机分为对照组 ,缺血 10 ,30 ,6 0 ,12 0min组及缺血 10 ,30 ,6 0 ,12 0min再灌注 4h组 ,每组 10只。通过结扎及放松右冠状动脉起始部制作窦房结缺血再灌注损伤模型 ,当达各预定时间点后 ,迅速切取窦房结组织固定 ,用TUNEL法检测窦房结细胞凋亡。结果 :①对照组、缺血10 ,30min组均未观察到明显的窦房结细胞凋亡现象。②缺血 6 0 ,12 0min组及缺血再灌注 4组中共有 6 8.3% (41/6 0 )的兔子窦房结细胞出现不同程度的凋亡现象 ,表明该部分兔子的窦房结动脉起源于右冠状动脉。③缺血 6 0 ,12 0min两组窦房结细胞凋亡率分别为 8.6 %与 16 .1% ,而缺血 10 ,30 ,6 0 ,12 0min再灌注 4h 4组中窦房结细胞凋亡率分别为 2 3.5 %、34.5 %、4 4 .7%与 31.2 %。结论 :缺血再灌注可诱导在体兔窦房结细胞凋亡 ,且随缺血时间延长 ,细胞凋亡率逐渐增加 ;再灌注组细胞凋亡率较相同时间缺血组明显增加 ,表明缺血再灌注损伤介导了窦房结细胞凋亡。

To study influence of ischemia reperfusion(IR) on apoptosis of sinoatrial node(SAN) cells in rabbits in vivo,Ninety healthy adult rabbits were divided randomly into control group,ischemia groups (I) 10(I 10 min ),30(I 30 min ),60(I 60 min ) and 120 min(I 120 min ) and IR groups (10,30,60 and 120 min ischemia followed by 4 h reperfusion respectively)(I 10 min R 4 h ,I 30 min R 4 h ,I 60 min R 4 h and I 120 min R 4 h ).Both the control group and each subgroup had 10 rabbits.IR injury model of SAN was established by occluding and loosening the start section of right coronary artery.The rabbits were sacrificed and the tissue of SAN was cut quickly at different time points.The apoptosis of SAN cells was detected by TUNEL staining.Results:①No obvious apoptosis of SAN cells was observed in control group,I 10 min group and I 30 min group.②Apoptosis of different degrees in SAN cells were found in 68.3%(41/60) rabbits in I 60 min group,I 120 min group and 4 subgroups of IR.③Apoptotic rates of SAN cells were 8.6% and 16.1% respectively in I 60 min group and I 120 min group,and that were 23.5%,34.5%,44.7%,and 31.2% respectively in I 10 min R 4 h ,I 30 min R 4 h ,I 60 min R 4 h and I 120 min R 4 h group.Conclusion:IR can induce apoptosis of SAN cells,and the apoptotic rates of SAN cells are increased with the prolongation of ischemic time.The apoptotic rate is higher in IR group than that in I group at the same time point.All these datas indicate IR injury mediate apoptosis of SAN cells.