CAJ | 학술논문

目的评价海马神经元自噬在七氟醚麻醉致幼龄大鼠认知功能障碍中的作用.方法雄性SD大鼠104只,7日龄,体重10～ 16 g,采用随机数字表法分为3组:对照组(C组,n=8)、七氟醚麻醉组(S组,n=48)和七氟醚麻醉+雷帕霉素组(SR,n=48).C组吸入60％026 h;S组吸入3.4％～3.6％七氟醚麻醉6 h;SR组于吸入七氟醚前1h时腹腔注射自噬激动剂雷帕霉素2 mg/kg,C组和S组腹腔注射等容量PBS.S组、SR组于七氟醚麻醉前1 h(T0)、麻醉结束即刻(T1)、麻醉结束后12 h(T2)、24 h(T3)和48 h(T4)时,取8只大鼠,采用Western blot法检测海马自噬蛋白微管相关蛋白1轻链3Ⅰ型(LC3Ⅰ)、LC3Ⅱ和Beclin-1的表达,计算LC3Ⅱ/LC3Ⅰ比值.麻醉结束后5周时行Morris水迷宫实验检测认知功能,记录逃避潜伏期、穿越平台次数和目标象限游泳时间.结果与T0时比较,S组T1-3时海马LC3Ⅱ和Beclin-1的表达下调,LC3 Ⅱ/LC3Ⅰ比值降低,SR组T1-4时海马LC3Ⅱ和Beclin-1的表达上调,LC3Ⅱ/LC3Ⅰ比值升高(P＜0.05);与C组比较,S组3～5d时逃避潜伏期延长,穿越平台次数减少,目标象限游泳时间缩短(P＜0.05),SR组上述各指标差异无统计学意义(P＞0.05);与S组比较,SR组3～5d逃避潜伏期缩短,穿越平台次数增加,目标象限游泳时间延长,T1-4时海马LC3Ⅱ和Beclin-1的表达上调,LC3Ⅱ/LC3Ⅰ比值升高(P＜0.05).结论海马神经元自噬减弱参与了七氟醚麻醉致幼龄大鼠认知功能障碍.
목적 평개해마신경원자서재칠불미마취치유령대서인지공능장애중적작용.방법 웅성SD대서104지,7일령,체중10～ 16 g,채용수궤수자표법분위3조:대조조(C조,n=8)、칠불미마취조(S조,n=48)화칠불미마취+뢰파매소조(SR,n=48).C조흡입60％026 h;S조흡입3.4％～3.6％칠불미마취6 h;SR조우흡입칠불미전1h시복강주사자서격동제뢰파매소2 mg/kg,C조화S조복강주사등용량PBS.S조、SR조우칠불미마취전1 h(T0)、마취결속즉각(T1)、마취결속후12 h(T2)、24 h(T3)화48 h(T4)시,취8지대서,채용Western blot법검측해마자서단백미관상관단백1경련3Ⅰ형(LC3Ⅰ)、LC3Ⅱ화Beclin-1적표체,계산LC3Ⅱ/LC3Ⅰ비치.마취결속후5주시행Morris수미궁실험검측인지공능,기록도피잠복기、천월평태차수화목표상한유영시간.결과 여T0시비교,S조T1-3시해마LC3Ⅱ화Beclin-1적표체하조,LC3 Ⅱ/LC3Ⅰ비치강저,SR조T1-4시해마LC3Ⅱ화Beclin-1적표체상조,LC3Ⅱ/LC3Ⅰ비치승고(P＜0.05);여C조비교,S조3～5d시도피잠복기연장,천월평태차수감소,목표상한유영시간축단(P＜0.05),SR조상술각지표차이무통계학의의(P＞0.05);여S조비교,SR조3～5d도피잠복기축단,천월평태차수증가,목표상한유영시간연장,T1-4시해마LC3Ⅱ화Beclin-1적표체상조,LC3Ⅱ/LC3Ⅰ비치승고(P＜0.05).결론 해마신경원자서감약삼여료칠불미마취치유령대서인지공능장애.
Objective To evaluate the role of autophagy in hippocampal neurons in cognitive dysfunction caused by sevoflurane anesthesia in juvenile rats.Methods One hundred four male SpragueDawley rats, aged 7 days, weighing 10-16 g, were randomly assigned into 3 groups using a random number table: control group (group C, n =8), sevoflurane anesthesia group (group S, n =48), and sevoflurane anesthesia + rapamycin group (group SR, n =48).Group C inhaled 60％ oxygen for 6 h.S and SR groups inhaled 3.6％ sevoflurane anesthesia for 6 h, and in addition, rapamycin 2 mg/kg was injected intraperitoneally at 1 h before of sevoflurane inhalation in group SR.The equal volume of phosphate buffer solution was given in C and S groups.At 1 h before sevoflurane anesthesia (T0) , immediately after the end of anesthesia (T1) , and at 12, 24 and 48 h after the end of anesthesia (T2-4) , 8 rats were randomly selected from S and SR groups to determine the expression of autophagy-related proteins microtubule-associated protein 1 light chain 3 (LC3) Ⅰ , LC3 Ⅱ and Beclin-1 in hippocampal neurons (by Western blot).The ratio of LC3 Ⅱ/LC3 Ⅰ was calculated.Morris water maze test was performed at 5 weeks after the end of anesthesia to assess the cognitive function.The escape latency, frequency of crossing the original platform, and duration of swimming spent at the target quadrant were recorded.Results Compared with the values at T0, the expression of LC3 Ⅱ and Beclin-1 was significantly down-regulated at T1-3 , and the ratio of LC3 Ⅱ/LC3 [was decreased in group S, and the expression of LC3 Ⅱ and Beclin-1 was significantly up-regulated at T1-4, and the ratio of LC3 Ⅱ/LC3 Ⅰ was increased in group SR (P＜0.05).Compared with group C, the escape latency was significantly prolonged, the frequency of crossing the original platform was reduced, and the duration of swimming spent at the target quadrant was shortened at 3-5 days in group S (P＜0.05) , and no significant change was found in the parameters mentioned above in group SR (P＞ 0.05).Compared with group S, the escape latency was significantly shortened, the frequency of crossing the original platform was increased, and the duration of swimming spent at the target quadrant was prolonged at 3-5 days, the expression of LC3 Ⅱ and Beclin-1 was up-regulated at T1-4 , and the ratio of LC3 Ⅱ/LC3Ⅰ was increased in group SR (P＜0.05).Conclusion Weakened autophagy in hippocampal neurons is involved in cognitive dysfunction caused by sevoflurane anesthesia in the juvenile rats.