益气化瘀方对腰神经压迫模型大鼠背根节神经细胞凋亡和caspase-3表达的影响

目的：观察益气化瘀方对腰神经根压迫损伤大鼠背根节神经细胞凋亡及半胱氨酸天冬氨酸蛋白酶3（caspase-3）的影响。方法：雄性SD大鼠40只随机分为假手术组、模型组、弥可保组和益气化瘀方组，每组10只。造模各组用自制胶块压迫于大鼠右侧L；神经根背根节处，假手术组仅切开皮肤和椎旁肌。造模后假手术组和模型组大鼠给予生理盐水灌胃，益气化瘀方组大鼠给予益气化瘀方煎剂灌胃，弥可保组大鼠肌肉注射弥可保。于造模10d后取右侧受压神经根，采用原位末端脱氧核苷酸转移酶标记法检测神经细胞的凋亡情况；分光光度法结合考马斯亮蓝法检测受压迫神经根caspase-3活性；实时荧光定量聚合酶链式反应法检测神经根组织caspase-3mRNA表达变化。结果：腰神经根受压迫后背根节的神经细胞凋亡明显增加，模型组大鼠神经细胞的凋亡指数高于假手术组（P〈0．01）；益气化瘀方和弥可保可减少背根节神经细胞的凋亡，两组大鼠神经细胞的凋亡指数低于模型组（P〈0．05）。模型组大鼠神经根组织caspase-3活性和mRNA表达明显增高，与假手术组比较差异有统计学意义（P〈0．05或P〈0．01）；益气化瘀方和弥可保可降低造模后大鼠神经根组织caspase-3活性及其mRNA表达，二者与模型组比较差异均有统计学意义（P〈0．01）。结论：腰神经根压迫可导致受压神经根组织caspsae-3的过表达和神经细胞凋亡的增加。益气化瘀方可抑制神经根组织caspase-3的过表达，减轻背根节神经细胞的凋亡。

Effects of Chinese herbal medicine Yiqi Huayu Recipe on apoptosis of dorsal root ganglion neurons and expression of caspase-3 in rats with lumbar nerve root compression

Objective： To observe the effects of Yiqi Huayu Recipe, a Chinese compound herbal medicine, on apoptosis of dorsal root ganglion （DRG） neurons and expression of caspase-3 in rats after lumbar nerve root compression injury. Methods： A total of 40 male Sprague-Dawley rats were randomly allocated into 4 groups： control group, untreated group, Methycobal group and Yiqi Huayu Recipe group. Surgery was performed on rats of untreated group, Methycobal group and Yiqi Huayu Recipe group to place a micro-silica gel on right L4 DRG, while control group received skin and paravertebral muscle incision only. Rats in Methycobal group and Yiqi Huayu Recipe group were given Methycobal by intramuscular injection and Yiqi Huayu Recipe intragastrically respectively. Rats in control group and untreated group received saline intragastrically as equal amount as Yiqi Huayu Recipe group. The compressed nerve roots were harvested at the 10th day after treatment. Apoptosis of DRG neurons was detected by terminal deoxynucleoitidyl transferase-mediated nick-end labeling. Caspase- 3 activity and mRNA expression in compressed nerve roots were detected with spectrophotography and realtime polymerase chain reaction respectively. Results： Apoptosis of DRG neurons was significantly increased in the rat model. The apoptosis index of untreated group was higher than that of control group （P〈0.01）. Yiqi Huayu Recipe and Methylcobal could reduce the apoptosis of DRG neurons, and both groups showed a lower apoptosis index than untreated group （P〈 0.01）. Caspase-3 activity and its gene expression were significantly increased in untreated group. The levels of caspase-3 activity and its gene expression in untreated group were higher than those in control group （ P〈 0.05 or P〈0.01）. Yiqi Huayu Recipe and Methylcobal could reduce the overexpression of caspase-3 mRNA, and statistically significant differences were found between the untreated group and Yiqi Huayu Recipe group or Methylcobal group （P〈0.01）. Conclusion： Lumbar nerve root compression results in overexpression of caspsae-3 in nerve root tissue and increase of DRG neuron apoptosis. Yiqi Huayu Recipe can inhibit the overexpression of caspase-3 and alleviate the apoptosis of DRG neurons after nerve injury.