Bax-抑制肽对新生鼠缺氧缺血性脑损伤神经细胞凋亡的抑制作用  

Anti-apoptosis effects of Bax-inhibiting peptide on hypoxia-ischemia induced neuroapoptosis in neonatal rats

作　　者：孙梦雅[1] 崔凯洁 王雯雯[1] 姜红[1] 秦苗[1] 彭祥莉 

机构地区：[1]青岛大学附属医院新生儿科,266003 [2]青岛市妇女儿童医院新生儿科

出　　处：《中国新生儿科杂志》2015年第5期372-376,共5页Chinese Journal of Neonatology

摘　　要：目的探讨Bax-抑制肽(BIP)对缺氧缺血性脑损伤(HIBD)新生鼠神经细胞凋亡的抑制作用及可能有效治疗的时间窗。方法选取182只7日龄新生Wistar大鼠,随机分为Sham组(假手术组,n=14)、HIBD组(对照组,n=84)、BIP组(实验组,n=84)3组。HIBD组和BIP组通过结扎左侧颈总动脉以及置于含氧8%的氮氧混合气中2 h建立HIBD模型,Sham组仅游离左侧颈总动脉,不结扎、不低氧处理。HIBD组和BIP组分别经左侧侧脑室注射生理盐水5μl和BIP5μg(5μl)。根据HIBD模型建立后注射BIP和生理盐水的时间不同,将HIBD组和BIP组分为0 h、6 h、12 h、24 h、48 h、72 h 6个亚组(n=14)。Sham组不注射任何药物。所有实验动物均于HIBD模型建立后7天处死,进行大脑海马组织病理检测、蛋白免疫印迹法(Western blot)检测、逆转录PCR(RT-PCR)测定,观察脑组织改变、半胱氨酸天冬氨酸蛋白酶3(Caspase-3)蛋白及Caspase-3 mRNA的含量。结果 BIP组0 h、6 h、12 h、24 h、48 h亚组病理损伤程度均较HIBD组相应亚组轻,两组72 h亚组无明显差异。BIP组0 h、6 h、12 h、24 h、48 h亚组Caspase-3蛋白及Caspase-3 mRNA含量均明显明显低于HIBD组,差异有统计学意义[Caspase-3蛋白:0 h(0.164±0.308)比(0.473±0.088),6 h(0.262±0.304)比(0.473±0.054),12 h(0.339±0.020)比(0.472±0.119),24 h(0.379±0.181)比(0.481±0.068),48 h(0.417±0.026)比(0.478±0.081);Caspase-3 mRNA:0 h(0.220±0.008)比(0.245±0.019),6 h(0.285±0.018)比(0.365±0.027),12 h(0.300±0.017)比(0.398±0.045),24 h(0.565±0.026)比(0.850±0.080),48 h(0.546±0.028)比(0.651±0.023),P<0.001],两组72 h亚组差异无统计学意义(P>0.05)。结论BIP可明显减少新生鼠HIBD后Caspase-3蛋白及Caspase-3 mRNA含量,抑制缺氧缺血后脑组织神经细胞凋亡;缺氧缺血后48 h内是BIP治疗HIBD的有效治疗时间窗,且越早应用治疗效果越好。Objective To study the anti-apoptosis effects and the proper time window of Bax- inhibitor peptide （BIP） in neural cells of neonatal rats with hypoxia-ischemia brain injury （ HIBD ）. Methods A total of 182 Wistar rat pups （7-day-old, PT） were randomly assigned into sham-operated group （ Sham Group, n = 14）, saline group （ NaC1 Group, n =84） and BIP group （ BIP Group, n = 84）. HIBD models were established ligating the left carotid artery along with 8% oxygen exposure for 2 hours in NaC1 Group and BIP Group. Left carotid arteries were dissected in Sham Group without further hypoxia-ischemia exposure. Normal saline （5 μl） and 5 μg BIP （5 p,1） were injected through the left lateral ventricular in NaC1 and BIP Group separately. Both NaC1 and BIP Group were further divided into six sub-groups as 0 h, 6 h,12 h,24 h ,48 h and 72 h subgroups （n =8） according to the time when saline and BIP were given. Sham Group received no drugs. All rats were sacrificed at day 7 after HIBD model establishment. The brain tissue pathology, alterations of Caspase-3 protein and Caspase-3 mRNA were studied. Results The pathological injury of BIP Group ameliorated comparing with NaC1 Group in 0 h,6 h,12 h,24 h and 48 h sub-groups , and without obvious differences in 72 h subgroup. Expression of Caspase-3 protein and mRNA in BIP Group were significantly decreased than NaC1 Group among 0 h, 6 h, 12 h, 24 h and 48 h sub-groups [ Caspase-3 protein：0 h（0. 164 ±0. 308）vs. （0. 473 ±0. 088） ,6 h （0.262 ±0.304）vs. （0.473 ±0.054）,12 h（0.339 ± 0.020）vs. （0.472 ±0. 119）,24 h（0.379 ± 0. 181 ）vs. （0. 481 ±0. 068） ,48 h（0. 417 ±0. 026） vs. （0. 478 ±0. 081 ） ;Caspase-3 mRNA：0 h（0. 220 ±0.008）vs. （0.245 ±0.019）,6 h（0. 285 ±0. 018）vs. （0.365 ±0.027）,12 h（0. 300 ±0.017）vs. （0.398±0.045）,24 h（0.565 ±0.026）vs. （0.850 ±0.080）,48 h （ 0. 546 ± 0. 028 ） vs. （0.651 ± 0. 023）,P 〈0. 001]. No significant differences existed in 7

关 键 词：Bax-抑制肽 缺氧缺血 脑 半胱氨酸天冬氨酸蛋白酶3 大鼠 

分 类 号：R722.1[医药卫生—儿科]