脑红蛋白对蛛网膜下腔出血大鼠早期脑损伤的保护作用

目的探讨脑红蛋白（NGB）对蛛网膜下腔出血（SAH）大鼠早期脑损伤的保护作用。方法将60只清洁级sD大鼠随机分为4组：正常组、假手术组、SAH组、治疗组（SAH＋腹腔注射氯化血红素）组。除SAH组30只外，其余每组10只大鼠。采用枕大池单次注血法建立大鼠SAH模型。采用免疫组化法和图像分析技术观测SAH后，不同时间大脑皮质颞叶的NGB免疫组化反应及平均吸光度A值；采用干湿法测量脑含水量，原位细胞凋亡检测法（TUNEL）检测颞叶神经元凋亡情况。结果①正常组和SAH后24h组平均吸光度4值分别是0．133±0．021和0．236±0．028：②sAH后颞叶皮质NGB阳性反应细胞迅速增加，24h达高峰，随后逐渐减少；③SAH组脑含水量为（77．5±0．4）％，治疗组脑含水量为（76．5±0．6）％，治疗组脑含水量较SAH组减少，差异有统计学意义（P〈0．05）；④治疗组和SAH组脑颞叶神经元凋亡程度为（9．8±2．4）％、（18．5±2．3）％。治疗组脑皮质神经元凋亡程度较SAH组降低（P〈0．05）。结论SAH后大鼠大脑皮质NGB阳性反应细胞呈动态变化。早期给予NGB能减少大鼠SAH模型的皮质神经元凋亡，降低脑水肿程度，具有明显的脑保护作用。

Neuroprotective effects of neuroglobin on early stage of brain injury after subarachnoid hemorrhage in rats

Objective To investigate the neuroprotective effects of neuroglobin（NGB） on early stage of brain injury after subarachnoid hemorrhage （ SAH ） in rats. Methods Sixty clean SD rats were randomly divided into four groups： normal, sham-operation, SAH, and treatment （SAH ± intraperitoneal injection of hemin） groups （n = 10 in each group, except in the SAH group, where n =30）. A rat model of SAH was induced by single cisterna magna blood injection. Immunohistochemistry and image analysis techniques were used to observe the NGB immunohistoebemical reaction and the mean optical density value of the temporal cortices at different time points after SAH; the dry and wet methods were used to measure brain water content; in situ apoptosis assay （TUNEL） was used to detect neuronal apoptosis in the temporal lobes. Results ①The mean optical density values in the normal group, and 24 h groups after SAH were 0. 133 ±0. 021 and 0. 236 ± 0. 028 respectively.② Ngb-positive cells in the temporal cortices increased rapidly after SAH. They reached the peak at 24 h, and then reduced gradually. ③ The brain water content in the SAH group was 77.5 ± 0.4%, and it in the treatment group was 76.5 ± 0.6%. The brain water content in the treatment group was less than that in the SAH group, and the difference was statistically significant （P 〈 0.05 ）.④The degrees of neuronal apoptosis in the temporal lobes were 9.8 ± 2.4% and 18.5 ±2.3% in the treatment group and the SAH group. The degrees of cerebral cortical neuronal apoptosis in the treatment group were significantly lower than those in the SAH group （ P 〈 0. 05 ）.Conclusion NGB-positive cells in rat cerebral cortex after SAH show dynamic changes. NGB given early may decrease cortical neuronal apoptosis of the rat model and reduce the degree of brain edema. It has obvious neuroprotective effects.