尼卡地平对脑缺血再灌注后海马CA1区细胞凋亡的影响

目的　研究沙土鼠短暂性脑缺血再灌注后细胞凋亡及尼卡地平处理的影响。方法　实验动物随机分为正常组、假手术组、对照组、尼卡地平处理组。正常组不进行手术操作 ,不进行脑缺血 ;假手术组只进行手术操作 ,不进行脑缺血 ;对照组阻断双侧颈总动脉 15min造成完全性前脑缺血模型 ;尼卡地平处理组在脑缺血前 30min给予腹腔注射尼卡地平 2mg/kg。用TdT介导的原位末端标记 (TUNEL)法来检测死亡神经元的DNA片段。HE染色计数海马CA1区 1mm长度内正常的锥体细胞数。结果　 (1)缺血再灌注后 2～ 4d ,对照组海马CA1区正常锥体细胞数比假手术组明显减少 (P <0 .0 1)。 (2 )缺血再灌注后 2～ 4d ,尼卡地平处理组海马CA1区正常锥体细胞数明显比对照组多 (P <0 .0 1)。 (3)尼卡地平处理组明显减少缺血再灌注后海马CA1区细胞凋亡 (P <0 .0 1)。结论　完全性前脑缺血再灌注后存在细胞凋亡 ;尼卡地平可抑制脑缺血再灌注后海马CA1区细胞凋亡。

Effect of Nicardipine on Apoptosis in Hippocampal CA1 Region after Transient Forebrain Ischemia in Gerbils

Objective To explor the neuronal apoptosis and effect of nicardipine after transient forebrain ischemia in gerbils. Methods Transient forebrain ischemia was induced by 15 minutes bila- teral commoncarotid occlusion.All gerbils were randomly divided into the normal group,sham operation group,control group and nicardipine group.Fragmented DNA was identified by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-labeling(TUNEL).The number of normal pyramidal cells in the hippocampal CA1 field in 1 mm length was counted with hematoxylin and eosin. Results (1) Two to four days after ischemia-reperfusion,the normal pyramidal cells in the hippocampal CA1 field in the control group were less than that in the sham operation group ( P < 0.01 ).(2) Two to four days after ischemia-reperfusion,the normal pyramidal cells in the hippocampal CA1 field in the nicardipine group were more than that in the control group ( P <0.01).(3) Nicardipine significantly decreased the number of apoptotic cells in the hippocampal CA1 field after ischemia-reperfusion ( P <0.01). Conclusion (1) Transient forebrain ischemia markedly produces apoptotic cell in hippocampus CA1 pyramidal neurons. (2) Nicardipine has inhibitory effect on ischemia-induced apoptosis of hippocampal CA1 region.