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听力学及言语疾病杂志JOURNAL OF AUDIOLOGY AND SPEECH PATHOLOGY
2002 Vol.10 No.4 P.244-246
豚鼠耳蜗单离外毛细胞游离钙的胆碱能调控
Cholinergic Regulation of Intracellular Free Calcium Concentrations in the Isolated Outer Hair Cells of the Guinea Pig Cochlea
肖自安
谢鼎华
伍伟景
杨曙
杨川
摘 要：目的观察胆碱能兴奋剂和拮抗剂对豚鼠耳蜗单离外毛细胞(OHC)内游离钙浓度([Ca2+]i)的影响,探讨OHC内[Ca2+]i的胆碱能调控机制.方法健康豚鼠15只处死,Hanks液中分离活性单离OHC,Fluo-3 / AM负载 30 min.分7组进行不同干预,包括乙酰胆碱(ACH,胆碱能M和N受体兴奋剂)、毒蕈碱( M受体兴奋剂)、阿托品(M受体拮抗剂)、庆大霉素(N受体拮抗剂)、加Hanks液对照组和 不加干预对照组;另1组为dHanks液中加ACh.用激光扫描共聚焦显微镜(Bio-Rad, 英国)观察OHC内 [Ca2+]i的变化.结果 Hanks液中不加干预试剂、加毒蕈碱、加Hanks液对照和无钙dHanks 液中加ACh等4组,[Ca2+]i在25～30 min内升幅<1.10倍.Hanks液中加ACh组[Ca 2+]i最高升幅平均为3.09倍;阿托品+ ACh组[Ca2+]i为2.92倍;庆大霉素+ A Ch组[Ca2+]i为1.81倍.结论豚鼠耳蜗传出神经递质ACh通过兴奋N受体,开放OHC的细胞膜钙离子 通道,使细胞外Ca2+内流外毛细胞内;[Ca2+]i增加需要细胞外液中钙离子存在.
关键词：耳蜗 外毛细胞 钙 胆碱能调控
文章编号：1006-7299(2002)04-0244-03
基金项目：国家自然科学基金资助项目(39770795)
作者简介：肖自安(1966-),男,湖南人,主治医师,博士,主要从事遗传性耳聋和听觉分子机理及耳鼻咽喉科临床研究
作者单位：肖自安（中南大学湘雅二医院耳鼻咽喉科和听力研究室,长沙,410011）
谢鼎华（中南大学湘雅二医院耳鼻咽喉科和听力研究室,长沙,410011）
伍伟景（中南大学湘雅二医院耳鼻咽喉科和听力研究室,长沙,410011）
杨曙（中南大学湘雅二医院耳鼻咽喉科和听力研究室,长沙,410011）
杨川（中南大学湘雅二医院,代谢内分泌研究所）
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