海马Chrnb4在老龄小鼠术后谵妄中的作用
Role of hippocampal Chrnb4 in postoperative delirium in aged mice
彭姮玥 1李靓静 1张明明 1何晓帆 1王臻 1赵晓春1
作者信息
- 1. 中国医科大学附属口腔医院麻醉科,沈阳 110002
- 折叠
摘要
目的 评价海马含β4亚基的烟碱型乙酰胆碱受体(Chrnb4)在老龄小鼠术后谵妄中的作用.方法 SPF级雄性C56BL/6J小鼠48只,18月龄,体质量29～35 g.采用随机数字表法分为6组:胫骨骨折手术组(TF组,n=6)、假手术组(Sham组,n=6)、胫骨骨折手术+阿地芬宁组(TA组,n=9)、胫骨骨折手术+对照溶剂组(TV组,n=9)、假手术+阿地芬宁组(SA组,n=9)和假手术+对照溶剂组(SV组,n=9).采用七氟烷麻醉下胫骨骨折手术制备术后谵妄模型.假手术为仅进行麻醉和皮肤切口并缝合.TA组、TV组、SA组、SV组于术前5 d置入脑室微量给药套管,每组再随机选取3只小鼠,置入海马CA1区微丝阵列电极.于术后30 min时,TA组和SA组脑室输注阿地芬宁(62.5 nmol/μl)2 μl,TV组和SV组给予对照溶剂2 μl,间断24 h给药,连续给予7 do TF组及Sham组于术后24 h时,采用实时定量PCR法检测海马组织Chrnb4 mRNA表达水平.TA组、TV组、SA组、SV组分别于术后第7、8天采用旷场实验及O迷宫实验评价冲动样行为;行为学实验结束后,采用免疫荧光染色法检测海马CA1区胶质纤维酸性蛋白(GFAP)及囊泡谷氨酸转运蛋白1(Vglut1)的表达,旷场实验期间记录小鼠海马CA1区局部场电位.结果 与Sham组相比,TF组海马Chrnb4 mRNA表达上调(P＜0.05);与TV组相比,TA组和SV组旷场实验中心路程百分比和O迷宫开放象限停留时间百分比降低,CA1区场电位β波功率降低,海马CA1区GFAP和Vglut1表达下调,GFAP+-Vglut1+共染面积减少(P＜0.05).SA与SV组各指标比较差异无统计学意义(P＞0.05).结论 海马Chrnb4可能参与了老龄小鼠术后谵妄的发生机制,该过程可能与抑制神经元兴奋性毒性有关.
Abstract
Objective To evaluate the role of hippocampal β4-Subunit-Containing Nicotinic Ace-tylcholine Receptors(Chrnb4)in postoperative delirium in aged mice.Methods Forty-eight SPF male C57BL/6J mice,aged 18 months,weighing 29-35 g,were assigned into 6 groups using a random number table method:tibial fracture group(TF group,n=6),sham operation group(Sham group,n=6),tibial fracture+adipenine group(TA group,n=9),tibial fracture+control vehicle group(TV group,n=9),sham operation+adipenine group(SA group,n=9),and sham operation+control vehicle group(SV group,n=9).The postoperative delirium model was prepared by tibial fracture under sevoflurane anesthe-sia.Tibial fracture was simulated by implanting a steel pin into the tibia and then clamping it,while sham group only received a longitudinal incision and suture after anesthesia.A microinjection cannula was implan-ted into the mouse skull at 5 days before developing the model in TA group,TV group,SA group and SV group.Three mice from each group were randomly selected for microelectrode implantation in the hippocam-pal CA1 area.Starting from 30 min after surgery,adipenine(62.5 nmol/μl)2 μl was infused into the cere-bral ventricle for 7 consecutive days in TA and SA groups,and vehicle(2 μl)was administered instead at a 24-h interval for 7 consecutive days in TV and SV groups.The expression of Chrnb4 mRNA in the hipp-ocampal tissues was detected by real-time quantitative polymerase chain reaction at 24 h after surgery.Un the 7th and 8th days after surgery,the open-field test and O-maze experiment were conducted to assess the impulsive-like behavior in TA,TV,SA and SV groups.After the behavioral test,the expression of glial fi-brillary acidic protein(GFAP)and vesicular glutamate transporter 1(Vglut1)in the hippocampal CA1 re-gion was detected by immunofluorescence staining.The local field potentials in the hippocampal CA1 region were recorded during the open field test.Results The expression of Chrnb4 mRNA in the hippocampal tis-sues was significantly up-regulated in TF group compared to Sham group(P＜0.05).Compared with TV group,the percentage of central path distance in the open field test and percentage of time spent in the open arms of the O-maze were significantly decreased,the power of β-waves in the CA1 field potentials was de-creased,the expression of GFAP and Vglut1 in the hippocampal CA1 region was down-regulated,and the co-staining area of GFAP+and Vglut1+was decreased in TA group and SV group(P＜0.05).There was no significant difference in each parameter between SA group and SV group(P＞0.05).Conclusions Hipp-ocampal Chrnb4 may be involved in the mechanism of postoperative delirium in aged mice,and this process may be related to inhibition of neuron excitotoxicity.
关键词
谵妄/术后认知并发症/老年人/受体,烟碱Key words
Delirium/Postoperative cognitive complications/Aged/Receptors,nicotinic引用本文复制引用
出版年
2024
NETL
NSTL
万方数据