血糖水平对大鼠脑挫裂伤后伤灶周围神经细胞中Bcl-2和Bax mRNA表达水平的影响  

The expression of Bcl-2 mRNA and Bax mRNA under different blood sugar levels after experimental brain injury in rats

作　　者：王仕国[1] 李俊[1] 戴学东[1] 范军民[1] 

机构地区：[1]南京市江宁医院神经外科,211100

出　　处：《江苏医药》2007年第12期1242-1244,共3页Jiangsu Medical Journal

摘　　要：目的研究大鼠脑挫裂伤后不同血糖水平对伤灶周围神经细胞中凋亡相关基因Bcl-2和Bax mRNA表达水平的影响。方法将60只健康雄性SD大鼠随机分成对照组和实验组,以自由落体法制造大鼠脑挫裂伤模型后,颈静脉置管输入50%葡萄糖溶液建立高血糖动物模型,对照组以相同方法输入等量生理盐水溶液。在伤后即刻、6、12、24、48h5个时间点,抽提大鼠伤灶周围组织总RNA,RT-PCR方法分析两组大鼠伤灶周围的脑组织中Bcl-2和Bax mRNA表达水平。结果正常脑组织中Bcl-2 mRNA表达几乎为阴性;脑挫裂伤后早期伤灶周围神经细胞Bcl-2 mRNA表达明显增加,在伤后24h达到高峰,之后渐下降。而正常脑组织中有Bax mRNA表达,脑挫裂伤后早期伤灶周围脑细胞Bax mRNA表达亦有明显增加,伤后12h达到高峰,之后渐下降。伤后各时间点实验组大鼠Bcl-2 mRNA的表达水平较对照组大鼠明显减低,而Bax mRNA表达则明显升高。结论脑挫裂伤后高血糖水平对挫裂伤灶周围神经细胞中Bcl-2基因的表达有抑制作用,而对Bax基因的表达则有促进作用。脑挫裂伤后高血糖水平会加重伤灶周围神经细胞的凋亡。Objective To explore the changes of Bcl-2 and Bax mRNA expression in the tissues around experimental brain injury of SD rats under different blood sugar levels. Methods Free falling body injury method was used to establish brain contusion model in 60 SD rats. The rats in group A was given injection of 50% dextrose through jugular vein, and the those in group B were injected normal saline. The expression levels of Bcl-2 and Bax mRNA in the tissues around brain contusion were measured by RT-PCR method at 0,6,12,24 and 48 h after injury. Results Nearly no expression of Bcl-2 mRNA was found in the normal brain tissues. Bcl-2 mRNA significantly increased in the brain tissues around brain contusion in early phase after injury and reached its maximum level at 24 hours after injury, then it dropped slowly. Bax mRNA was expressed in normal brain tissues, and its expression significantly increased in the brain tissues around brain contusion in early phase after injury. Bax mRNA reached its peak at 12 hours after injury,and dropped thenafter. The expression of Bax mRNA enhanced greatly in group A compared to that in group B at each time point after injury, but the expression of Bcl-2 mRNA was on the contrary. Conclusions Hyperglycemia can enhance the expression of Bax mRNA and decrease the expression ofBcl-2 mRNA in the brain tissues around brain injury focus in SD rats. Hyperglycemia can aggravate brain cell apoptosis around focus after brain injury.

关 键 词：细胞凋亡 Bcl-2 Bax 脑挫裂伤 血糖 

分 类 号：R64[医药卫生—外科学]