三七总皂苷对新生鼠窒息后脑细胞凋亡及凋亡蛋白Bax表达的影响

The effect of total panax notoginseng naponinsin on the apoptosis of brain cells and the expression of apoptotic protein bax in newbron rat after asphyxia

目的了解三七总皂苷(TPNS)对新生SD大鼠窒息后脑细胞凋亡及凋亡蛋白Bax表达的影响。方法出生7 d的SD大鼠88只,随机分为对照组(n=8),窒息+NS组(n=40),窒息+TPNS组(n=40)。将大鼠放入55 ml的磨口瓶中,瓶中放入5 g钠石灰,待新生鼠安静后,窒息+TPNS组及窒息+NS组塞紧瓶塞30 min,取出后复氧120 min,窒息后即刻分别腹腔注射TPNS 100 mg/kg、同等容积0.9%盐水,q 12 h重复腹腔注射,注射后放回母鼠身边继续喂养,分别于窒息后6 h、24 h、48 h、72 h、7 d处死;对照组放入55 ml的磨口瓶中30 min不塞瓶塞,取出后复氧120 min,放回母鼠身边继续喂养,6 h后全部处死。采用原位缺口末端标记(TUNEL)法检测脑细胞凋亡率,免疫组织化学法检测Bax蛋白的表达。结果窒息+NS组及窒息+TPNS组均可见凋亡细胞,明显高于对照组,窒息+NS组(除6 h外)凋亡细胞数明显高于窒息+TPNS组,差异均有统计学意义(P均<0.05);窒息+NS组及窒息+TPNS组Bax表达明显高于对照组,窒息+TPNS组Bax表达明显低于窒息+NS组,差异均有统计学意义(P均<0.05)。结论细胞凋亡是窒息后脑损伤的主要表现形式,主要是通过凋亡蛋白Bax调节,TPNS可减少脑组织Bax的表达,减少凋亡细胞数目,对窒息所致的脑损伤有保护作用。

Objective To study the effect of total panax notoginseng saponinsin （TPNS） on the apoptosis of brain cells and the expression of apoptotic protein Bax in neonatal SD rats after asphyxia. Methods Eighty-eight 7-day-old newborn SD rats were randomly divided into control group （n=8）, 0.9% saline-treated group （n=40） and TPNS-treated group （n=40）. Newborn rats were placed in the wide-necked 55 ml bottles with 5 gram soda-lime. Plug the caps onto bottles in saline-treated group and PNS-treated group for 30 minutes after the rats were quiet. Then the rats were re-oxygenated for 120 minutes. The rats in TPNS-treated group were given 100 mg/kg TPNS. The rats in saline-treated group were injected intraperitoneally with equal volume of 0.9% saline solution; the same dose of 0.9% saline solution or TPNS was intraperitoneaUy injected every 12 hours. After injection, rats were put back to dams for breastfeeding. Rats in saline-treated group and TPNS-treated group were sacrificed at 6 h, 24 h, 48 h, 72 h and 7 d after asphyxia. Control rats were placed in the wide-necked 55 ml bottle without soda lime, and then were sacrificed at 6 h. The apoptotic rate of brain cells was tested by terminal deoxynucleotidyl transferase biotin-dutp nick end labeling （TUNEL） assay and expression of Bax protein was tested by immunohistochemistry. Results Rats in saline-treated group and TPNS-treated group had apoptosis in brain, and it was significantly more severe than in the control group （P〈0.05）. The number of apoptotic cells in saline-treated group （except at 6 h） was significantly higher than that in TPNS-treated group （P〈0.05）. The expression of bax in saline-treated group and TPNS-treated group was significantly higher than that in the control group （P〈0.01）. The expression ofbax in TPNS-treated group was significantly lower than that in saline-treated group （P〈0.05）. Conclusions Apoptosis is the main manifestation of brain damage after asphyxia. The apop- tosis in brain is mainly regulated by apoptosis protein Bax. The application of TPNS can reduce the expression of Bax in braintissue, and reduce the number of apoptotic cells in brain. It is indicates that TPNS has significant protective effect on asphyxia-induced brain damage.