香烟烟雾吸入对大鼠局灶性脑缺血细胞凋亡及脑梗死体积的影响

EFFECT OF CIGARETTE SMOKING ON EXPRESSION OF APOPTOSIS OF NEUROCYTE AND INFARCTION VOLUME IN RATS

目的探讨不同剂量与不同时程的香烟烟雾吸入对大鼠局灶性脑缺血细胞凋亡及脑梗死体积的影响。方法参考Chow方法建立大鼠吸烟模型,将60只大鼠随机分成6组,A组:长期大量吸烟组;B组:长期小量吸烟组;C组:短期吸烟组;D组:戒烟组;E组:脑缺血对照组;F组:正常对照组。每组10只大鼠。参照Zealonga方法制备大鼠局灶性脑缺血模型。观察大鼠局灶性脑缺血2h再灌注24h时大鼠脑梗死体积和凋亡细胞数的改变。结果①各吸烟组脑梗死灶体积均大于缺血对照组(P<0.05),脑梗死体积随吸烟的量和时程的增加而增加。戒烟组脑梗死灶体积与缺血对照组比较差异无统计学意义(P>0.05)。②正常组大鼠脑组织未见凋亡细胞。其他各组大鼠的大脑皮质和海马区均出现凋亡细胞,以海马区出现为著,各吸烟组大鼠的凋亡细胞数与缺血对照组比较差异有统计学意义(P<0.01)。戒烟组脑凋亡细胞与缺血对照组比较差异无统计学意义(P>0.05)。结论吸烟可使局灶性脑缺血大鼠脑梗死体积增加,加重局灶性脑缺血大鼠脑神经细胞的凋亡,且与吸烟量和时程间存在剂量效应关系。

Objective To explore the correlation among different doses and courses of cigarette smoking on rat, immunoactivities of the apoptosis of neurocytes and the infarction volume in rat brain. Methods Preparation of animal models： according to Chow et al＇s cigarettes perfused rat model; healthy wistar rats were randomly divided into 6 groups of 10 animals for each one. （A） long - term and large - dose smoking group. （B） long - term and small - dose smoking group. （C）short- term smoking group. （D）giving- up smoking group. （E）none- smoking control group. （F） normal control group. After 12 weeks, the rat model with ischemic brain was prepared according to Zea longgs methods. The infarction volume of the rats＂ brain and apoptotic positive cells 2h and 24h after ischemic reperfusion. Results ①Except the giving- up smoking group, the infarction volume of the smoking groups were bigger than that of the none- smoking control group, the infarction volume was increased with the quantity of cigarettes and smoking courses（P〈0.05）. ②Apoptotic positive cells were found in the cortex and hippocampus in all smoking groups, especially in the long - term and large- dose smoking group, and there were significant difference between the smoking groups and the none- smoking control group （P〈0.01）. Conclusion Smoking would aggravate the apoptosis of neurocytes and the damage of brain after rats MCAO, which would become serious with the increment of the quantity of cigarettes and smoking courses.