Mg^(2+)对兔脑继发性脑损伤中细胞凋亡影响的实验研究

Experimental study of Mg^(2+) on effects of cell apoptosis of rabbit secondary brain injury

目的探讨Mg2+对兔脑继发性脑损伤中细胞凋亡影响的实验情况。方法选择新西兰大白兔50只,随机分为实验组、对照组和假手术组,实验组及对照组各20只,假手术组10只;实验组及对照组动物在脑外伤后早期静脉使用硫酸镁后,通过对挫伤灶周围脑组织的病理学检查、透视电镜检查及细胞调亡的检测,分析镁离子对脑继发性损害中细胞调亡的影响。结果对照组脑损伤6 h后,组织病理学显示损伤病灶出血、组织间隙增宽、周围细胞水肿,脑损伤后48 h最为显著,损伤病灶内出现胞膜结构完整、细胞核固缩深染的神经细胞,即神经细胞凋亡,凋亡细胞相对密集;实验组神经细胞变性坏死较少、脑水肿较轻,两侧病变差异不显著;正常脑组织内TUNEL阳性细胞表达较少,损伤6 h的标本出现TUNEL散在少量阳性细胞,两组标本中的TUNEL阳性细胞数量随着损伤时间的延长而逐渐增加,峰期为24 h,实验组各时段的TUNEL阳性细胞显著低于同时段的对照组,差异有统计学意义(P<0.05)。结论镁离子可降低兔脑继发性脑损伤中神经细胞凋亡数量,对脑损伤神经细胞起到保护作用。

Objective To explore the experiment of Mg2+on effects of cell apoptosis of rabbit secondary brain injury.Methods Fifty New Zealand white rabbits, irrespective of genders were selected, they were randomly divided into experimental group, control group and operation control group, 20 rats in each group of the experimental group and the control group, 10 rabbits were in the sham operation group; animal were used magnesium sulfate after brain injury in the early vein,through the pathology examination of brain tissue around contusion foci, X-ray examination of electron microscopy and cell apoptosis detection, the effect of magnesium ion on the cell apoptosis in secondary brain damage was analyzed. Results The control group after 6 h of brain injury, pathology showed focus of the lesions appeared haemorrhage, the organization gap widened, peripheral edema, 48 h after brain injury was most significant, the lesions appeared cell membrane structure complete, the nucleus pycnosised nerve cells,that was to say, neural cell apoptosis,apoptotic cells were relatively dense; Neural cell degeneration and necrosis of experimental group were less, brain edema was lighter, there were no significant differences on both sides of the lesions; the expression of TUNEL positive cells in normal brain tissue was less, 6-hour-injury specimens appeared TUNEL powder in a small number of positive cells, the number of TUNEL positive cells of specimens of two groups increased with the prolongation of injury time,the peak period was 24 hours, TUNEL positive cells at different stages in the experimental group were significantly lower than those of the control group at the same time segment, the difference had statistical significance(P <0.05).Conclusion Magnesium ions can reduce the number of nerve cell apoptosis of rabbit secondary brain injury, play a protective role in injury of cerebral nerve cells.