脑缺血后不同再灌注条件对大鼠脑ASICs3表达的影响

Influencing of ASICs3 expression under different reperfusion condition after SD rats brain ischemia

[目的]研究SD大鼠脑在缺血后不同再灌注流量时可渗性钙离子酸敏感离子通道(ASICs)的表达特点。[方法]SD大鼠随机分3组,A组(适应性再灌注组,n=15)为缺血后逐步开放脑血流量10 min,B组(一次性再灌注组,n=15)为缺血后完全开放脑血流量10 min,C组(对照组)为缺血重度损伤组。分别观察海马CA区ASICs的表达,脑血流量的变化及缺血大脑半球的pH改善状况和海马区形态学改变。[结果]重度脑损害后A组再灌注流量由(0.5±0.1)mL/min逐渐增加到(3.2±0.6)mL/min,B组再灌注流量由(0.5±0.1)mL/min增加到(6.2±1.5)mL/min,灌注流量明显增加。A组pH值改善最为明显,由7.15±0.05上升到7.38±0.04(P<0.05),而B组pH值由7.15±0.05变为7.10±0.04,A组pH值与B、C组相比差异有显著性意义,P<0.05。B组颈总动脉脑血流量值与A、C组相比差异有显著性意义,P<0.05。海马CA区ASICs的表达B组较A组明显上调,而A组可以看到较B组更多密集的正常神经元细胞。[结论]ASICs3的表达和脑缺血不同再灌注方式有相关性,适应性再灌注流量有较轻的脑损害作用。

[Objective] The purpose of the study was to evaluate the role of ASICs in the different reperfusion inflow in SD rats,and the relationship between acidosis and ASICs after global ischemic insults.[Methods] The SD rats ischemic models were divided into three groups randomly：group A：adaptive ischemia-reperfusion group;group B：one-time ischemia-reperfusion group;group C： severe cerebral ischemic injury group.The SD rats were made by bilateral carotid artery 10 min occlusion.After the whole reperfusion 10 min and different reperfusion inflow（1/2,1/1）,the ASICs3 gene expression and pH insult and morphology and cerebral blood flow of hippocampus CA1 region were all observed.[Results] After the severe brain damage,the reperfusion flow of group A was gradually from（0.5±0.1）mL/min to（3.2±0.6）mL/min,whereas the reperfusion flow of the group B was from（0.5±0.1）mL/min to（6.2±1.5）mL/min,the perfusion flow was significantly increasing.The value of pH in group A was the most significant improvement,increased from 7.15±0.05 to 7.38±0.04（P0.05）,while the value of pH in group B was from 7.15±0.05 to 7.10±0.04.The value of pH in group A respectively compared with the group B and C,the differences were statistically significant（P0.05）;CCA cerebral blood flow values in group B respectively compared with the group A and C,the differences were statistically significant（P0.05）.The gene expression of ASICs in group B was obviously up-regulated than that in group A,whereas there were more normal neuron cells in group A than that in group B.[Conclusion] There was highly relationship between ASICs expression and different reperfusion inflow,and low reperfusion inflow improving had less cerebral ischemic insult.