CAJ | 학술논문

目的探讨c-Jun氨基末端激酶(the c-Jun N-terminal kinase,JNK)信号通路对异氟醚诱导新生大鼠海马神经细胞凋亡以及对磷酸化JNK、Bcl-2和Bax蛋白表达的影响.方法 48只出生后7d(Py7)的新生大鼠按照随机数的方法随机均分为DMSO对照组(D组)、JNK抑制剂SP600125对照组(SP30组)、异氟醚+DMSO组(Iso+D组)和异氟醚+SP600125组(Iso+ SP30组).对照组吸入空气,异氟醚组吸入1.1％异氟醚4h.麻醉前20 min,幼鼠根据分组分别侧脑室注射SP600125 30 μg或者12％ DMS0 5μl.麻醉结束后6h,部分幼鼠灌注取脑,TUNEL荧光染色检测脑海马CA1区神经细胞凋亡(n=6)；部分幼鼠取新鲜脑皮质,Western blotting法检测磷酸化JNK、Bcl-2和Bax蛋白表达的变化(n=6).组间资料的比较采用单因素方差分析.结果幼鼠海马CA1区的TUNEL阳性细胞数比较,Iso+D组[(135.72±21.26)个/mm2]比D组[(24.07±1.35)个/mm2]增加5倍(P＜0.01)；与Iso+D组相比,Iso+ SP30组[(42.49±5.56)个/mm2] CA1区的TUNEL阳性细胞数降低了84％ (P＜0.05).Iso+D组磷酸化JNK P46表达比D组增加44.1％ (P＜0.01),而Iso+ SP30组显著降低了磷酸化JNK P54 (p＜ 0.05)和P46(P＜ 0.01)的表达.Iso+D组Bax表达比D组增加1.5倍(P＜0.05),Bcl-2蛋白表达比D组下降42.2％ (P＜0.05)；而Iso+ SP30组Bax表达下降(P＜0.05),Bcl-2蛋白表达上调(P＜0.01).D组与SP30组TUNEL阳性细胞数,磷酸化JNK,Bcl-2和Bax蛋白表达差异均无统计学意义.结论 JNK信号通路激活促进了异氟醚诱导发育期大鼠海马神经细胞凋亡,SP600125通过维持Bcl-2,降低Bax表达产生抑制凋亡作用.
목적 탐토c-Jun안기말단격매(the c-Jun N-terminal kinase,JNK)신호통로대이불미유도신생대서해마신경세포조망이급대린산화JNK、Bcl-2화Bax단백표체적영향.방법 48지출생후7d(Py7)적신생대서안조수궤수적방법수궤균분위DMSO대조조(D조)、JNK억제제SP600125대조조(SP30조)、이불미+DMSO조(Iso+D조)화이불미+SP600125조(Iso+ SP30조).대조조흡입공기,이불미조흡입1.1％이불미4h.마취전20 min,유서근거분조분별측뇌실주사SP600125 30 μg혹자12％ DMS0 5μl.마취결속후6h,부분유서관주취뇌,TUNEL형광염색검측뇌해마CA1구신경세포조망(n=6)；부분유서취신선뇌피질,Western blotting법검측린산화JNK、Bcl-2화Bax단백표체적변화(n=6).조간자료적비교채용단인소방차분석.결과 유서해마CA1구적TUNEL양성세포수비교,Iso+D조[(135.72±21.26)개/mm2]비D조[(24.07±1.35)개/mm2]증가5배(P＜0.01)；여Iso+D조상비,Iso+ SP30조[(42.49±5.56)개/mm2] CA1구적TUNEL양성세포수강저료84％ (P＜0.05).Iso+D조린산화JNK P46표체비D조증가44.1％ (P＜0.01),이Iso+ SP30조현저강저료린산화JNK P54 (p＜ 0.05)화P46(P＜ 0.01)적표체.Iso+D조Bax표체비D조증가1.5배(P＜0.05),Bcl-2단백표체비D조하강42.2％ (P＜0.05)；이Iso+ SP30조Bax표체하강(P＜0.05),Bcl-2단백표체상조(P＜0.01).D조여SP30조TUNEL양성세포수,린산화JNK,Bcl-2화Bax단백표체차이균무통계학의의.결론 JNK신호통로격활촉진료이불미유도발육기대서해마신경세포조망,SP600125통과유지Bcl-2,강저Bax표체산생억제조망작용.
Objective To investigate the effects of the c-Jun N-terminal kinase (JNK)pathway on isoflurane induced neuronal apoptosis and the proteins expression of phospho-JNK,Bcl-2 and Bax in the hippocampi of neonatal rats.Methods Forty-eight neonatal rats at postnatal day 7 (P7) were randomly assigned into 4 groups:DMSO control group (group D),SP600125 control group (group SP30),isoflurane + DMSO group (group Iso +D),isoflurane + SP600125 group (group Iso + SP30).Rats were exposed to air (control group) or 1.1％ isoflurane (isoflurane group) for 4 h.The JNK inhibitor SP600125 at 30 μg or 12％ DMSO 5 μl was intraventricularly administered 20 min before the exposure.The brains of some rats in each group were perfused and embedded by paraffin 6 h after the exposure.Neuronal apoptosis in the hippocampi CA1 area was detected by TUNEL (n =6).The fresh hippocampi of other rats in each group were dissected 6 h after the exposure and the proteins expression of phospho-JNK,Bcl-2 and Bax were detected by Western blot (n =6).One way ANOVA were used for data analysis among groups.Results The number of TUNEL positive cells in the hippocampal CA1 regions in group Iso +D (135.72 ±21.26 per mm2) increased by 5 folds compared with group D (24.07 ± 1.35 per mm2) (P＜0.01) ;while the number of apoptotic cells in group Iso + SP30 (42.49 ± 5.56 per mm2) decreased by 84％ (P ＜ 0.05)compared with group Iso + D.The expression of phospho-JNK p46 kd in group Iso + D increased by 44.1％ (P ＜0.01),while both phospho-JNK at p46kd and at p54kd in group Iso + SP30 decreased significantly (P＜0.05,P ＜0.01) compared with group Iso + D.The protein expression of Bax increased 1.5 folds (P＜0.05) and Bcl-2 decreased by 42.2％ (P＜0.05) in group Iso + D compared to group D;while SP600125 significantly decreased expression of Bax (P ＜0.05) and increased expression of Bcl-2 (P＜0.01).Conclusion JNK activation contributes to isoflurane-induced neuroapoptosis in the developing brain.Maintaining Bcl-2 expression and inhibiting Bax expression may be involved in the neuroprotective effects of SP600125.