双苯氟嗪对脑缺血再灌注损伤后细胞凋亡的影响

目的研究双苯氟嗪对局灶性脑缺血再灌注损伤后细胞凋亡的影响。方法采用endothelin1诱导的大鼠局灶性脑缺血再灌注模型,流式细胞术检测大脑皮层和纹状体神经细胞凋亡百分率、Bcl2和Bax蛋白表达量。结果假手术组皮层和纹状体细胞凋亡率低,分别为(1.26±0.15)%和(2.50±0.35)%,溶剂组细胞凋亡率明显增高,分别为(9.34±1.22)%和(10.58±1.44)%;双苯氟嗪可以降低皮层和纹状体细胞凋亡率,并呈现明显的剂量依赖关系〔皮层:10mg·kg-1组(7.92±0.76)%,20mg·kg-1组(6.78±0.77)%,40mg·kg-1组(6.00±0.71)%,r=0.9559,P<0.01;纹状体:10mg·kg-1组(9.76±1.47)%,20mg·kg-1组(8.52±0.60)%,40mg·kg-1组(7.22±1.39)%,r=0.9845,P<0.01〕。Flu20mg·kg-1组可以降低缺血后大脑皮层的细胞凋亡百分率(8.12±0.94)%(P<0.05),但对纹状体细胞凋亡百分率无明显影响(P>0.05)。对Bcl2和Bax蛋白表达量的测定结果显示,假手术组皮层和纹状体均显示高水平的Bcl2表达,Bcl2和Bax比值最高,分别为:皮层1.30±0.08,纹状体1.64±0.10;溶剂组皮层和纹状体Bax表达增加,Bcl2和Bax比值明显低于假手术组,为1.03±0.12和1.00±0.04;Dip20、40mg·kg-1可以明显增加Bcl2表达,皮层和纹状体的Bcl2和Bax比值均高于溶剂组,而Dip10mg·kg-1组和Flu20mg·kg-1组不能对抗Bcl2和Bax比值的降低。结论双苯氟嗪可以明显抑制脑缺血再灌注损伤后神经细胞凋亡,其抗凋亡作用与增加Bcl2表达有关。

Effects of dipfluzine on cell apoptosis after cerebral Ischemia-reperfusion in rats

Aim To study the effects of dipfluzine (Dip) on cell apoptosis after focal cerebral ischemia-reperfusion injury in rats. Methods Endothelin-1 induced focal cerebral ischemia-reperfusion model in rat was used in experiment. The cell apoptosis, the expressions of Bcl-2 and Bax proteins were observed by flow cytometric analysis. Results The tissues from the solvent group showed remarkably high apoptotic percentages with(9.34±1.22)% in cortex and(10.58±1.44)% in striatum, respectively, in contrast with(1.26±0.15)% in cortex and(2.50±0.35)% in striatum in sham group. Dipfluzine could decrease the cell apoptosis in cortex and striatum and showed a close correlation with the dose increment, which were (7.92±0.76)% in 10mg·kg -1 group, (6.78±0.77)% in 20 mg·kg -1 group, and (6.00±0.71)% in 40 mg·kg -1 group in cortex (r=0.9559, P<0.01);(9.76±1.47)% in 10 mg·kg -1 group,(8.52±0.60)% in 20 mg·kg -1 group, and(7.22±1.39)% in 40 mg·kg -1 group in striatum (r=0.9845, P<0.01). Flu 20 mg·kg -1 could reduce the apoptotic percentage in cortex (P<0.05), but not in striatum(P>0.05). The determination of Bcl-2 and Bax by flow cytometric analysis indicated that sham group showed high expression of Bcl-2 both in cortex and striatum and the ratio of Bcl-2 and Bax were the highest,they were 1.30±0.08 in cortex and 1.64±0.10 in striatum, respectively. The expression of Bax in solvent group was increased and the the ratio of Bcl-2 and Bax were 1.03±0.12 in cortex and 1.00±0.04 in striatum, significantly lower than those in sham group (P<0.01). The ratio of Bcl-2 and Bax in cortex and striatum were significantly increased after treatment of Dip 20 mg·kg -1 and Dip 40 mg·kg -1, compared with solvent group. But Dip 10 mg·kg -1 and Flu 20 mg·kg -1 had no preventive effects on the reduction of the ratio of Bcl-2 and Bax. Conclusion Dipfluzine significantly reduced the cell apoptosis induced by focal cerebral ischemic-reperfusion injury. The anti-apoptotic effect of Dipfluzine was related to the increment of the Bcl-2 expression.