碱性成纤维细胞生长因子提高大鼠脑缺血/再灌注损伤后突触可塑性的机制研究  

Basic fibroblast growth factor promotes synaptic plasticity in rats after cerebral ischemia/reperfusion injury

作　　者：杨开令 张亚星 高宇容 周颖 巫芳华 刘微[1] YANG Kailing;ZHANG Yaxing;GAO Yurong;ZHOU Ying;WU Fanghua;LIU Wei(Basic Medical College,Guangzhou University of Chinese Medicine,Guangzhou 510006,China)

机构地区：[1]广州中医药大学基础医学院,广东广州510006

出　　处：《中国病理生理杂志》2023年第3期393-399,共7页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目(No.81673772,No.81900376);广东省中医药局科研项目(No.20221116)。

摘　　要：目的:探讨碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF)提高大鼠脑缺血/再灌注损伤后突触可塑性的机制。方法:构建大鼠大脑中动脉栓塞(middle cerebral artery occlusion,MCAO)模型,缺血2h后再灌注,随机分为缺血/再灌注损伤组(MCAO/R组)、MCAO/R+bFGF组、MCAO/R+成纤维细胞生长因子受体1(FGFR1)抑制剂组和MCAO/R+bFGF+Gap26[缝隙连接蛋白43(connexin 43,Cx43)抑制剂]组,另设假手术组作为对照,每组6只。bFGF和Gap26于术后第3天腹腔注射(剂量分别为100μg/kg,25μg/kg,每天1次),FGFR1抑制剂于术后第3天灌胃给药(3 mg/kg,每天2次),7 d后取材。采用Western blot检测缺血侧海马组织中Cx43的表达;通过免疫荧光双标染色标记FGFR1与星形胶质细胞标志物胶质细胞原纤维酸性蛋白(glial fibrillary acidic protein,GFAP)的表达;免疫荧光染色观察突触小泡蛋白(synaptophysin,SYN)和生长相关蛋白43(growth-associated protein-43,GAP-43)在缺血侧海马组织的表达情况。结果:与假手术组相比,脑缺血/再灌注损伤后海马组织中Cx43表达增多(P<0.05);与MCAO/R组相比,MCAO/R+bFGF组中Cx43表达显著增多(P<0.05),而FGFR1抑制剂组Cx43的表达显著减少(P<0.05),同时FGFR1与星形胶质细胞标志物GFAP表达定位高度重合;脑缺血/再灌注损伤后SYN和GAP-43的表达增多,bFGF可显著增加SYN和GAP-43的表达(P<0.05),而联合使用Gap26后bFGF对SYN和GAP-43表达的增强作用被显著抑制(P<0.05)。结论:bFGF可能通过Cx43促进SYN和GAP-43的表达,进而提高大鼠脑缺血/再灌注损伤后的突触可塑性。AIM To explore the potential mechanisms of basic fibroblast growth factor(bFGF)in promoting synaptic plasticity after cerebral ischemia/reperfusion injury.METHODS Middle cerebral artery occlusion(MCAO)was used to establish the model of focal ischemia,and reperfusion was performed after 2 h of ischemia.Rats were randomly divided into model group(MCAO/R group),MCAO/R+bFGF group,MCAO/R+fibroblast growth factor receptor 1(FGFR1)inhibitor group,and MCAO/R+bFGF+Gap26[a specific inhibitor of connexin 43(Cx43)]group.bFGF was given intraperitoneally at the dose of 100µg/kg once a day.Gap26 was intraperitoneally injected at the dose of 25µg/kg once a day.FGFR1 inhibitor was given by gavage(3 mg/kg)twice a day.These drugs were administered from day 3 after MCAO/R to avoid their influence in acute phase.At day 7,tissue samples were collected for the following detection.Western blot was used to measure the protein level of Cx43 in hippocampal tissues.The expression levels of FGFR1,astrocyte marker glial fibrillary acidic protein(GFAP),and synaptic plasticity-related proteins such as synaptophysin(SYN)and growth-associated protein-43(GAP-43)were measured by immunofluorescent staining.RESULTS Compared with MCAO/R group,the expression level of Cx43 was up-regulated by bFGF(P<0.05),and down-regulated by FGFR1 inhibitor(P<0.05).FGFR1 was mainly co-localized with astrocyte marker GFAP.In addition,Gap26 inhibited the beneficial effects of bFGF on synaptic plasticity-related proteins SYN and GAP-43.CONCLUSION bFGF may promote the expression of SYN and GAP-43 through Cx43,thus improving synaptic plasticity after cerebral ischemia/reperfusion injury in rats.

关 键 词：碱性成纤维细胞生长因子 脑缺血/再灌注损伤 突触可塑性 缝隙连接蛋白43 

分 类 号：R743[医药卫生—神经病学与精神病学] R363.2[医药卫生—临床医学]