期刊文献+

豚鼠Ⅱ型前庭毛细胞乙酰胆碱敏感性钾电流的钙离子依赖性 被引量:2

Dependence of Ca^(2+) on the acetylcholine-sensitive current in guinea pig type Ⅱ vestibular hair cells
原文传递
导出
摘要 目的研究豚鼠Ⅱ型前庭毛细胞乙酰胆碱(acetylcholine,ACh)敏感性钾电流对钙离子的依赖性。方法应用全细胞膜片钳技术研究新鲜单离的豚鼠Ⅱ型前庭毛细胞ACh-敏感性钾电流在细胞内外钙离子浓度改变时其电流幅值的变化。结果①细胞外ACh激活一缓慢持久的外向性钾电流,其反转电位为(-70±10)mV;②ACh-敏感性钾电流电流对细胞外四乙胺(10mmol/L)敏感,而对细胞外4-氨基吡啶(100μmol/L)不敏感;③ACh-敏感性钾电流的幅值大小依赖于细胞外的钙离子浓度,无钙外液中ACh激活一很小的电流,4mmol/L外钙溶液中ACh-敏感性钾电流的幅值达到最大值,而0·5mmol/L外钙溶液中ACh-敏感性钾电流的幅值抑制至(36·5±6·5)%;④细胞内三磷酸肌醇-钙离子释放过程不参与ACh-敏感性钾电流的激活,细胞内透析肝素8mg/ml后30min,ACh-敏感性钾电流的幅值没有明显改变;⑤ACh敏感性钾电流对钙通道阻断剂Cd2+敏感。结论豚鼠Ⅱ型前庭毛细胞ACh-敏感性钾电流的激活依赖于细胞外的钙离子浓度,ACh与豚鼠Ⅱ型前庭毛细胞胆碱能受体结合后,首先激活膜上钙通道引起细胞外钙离子内流,毛细胞内游离钙离子浓度的升高进一步激活钙依赖性钾电流。 Objective To explore the dependence of Ca^2+ on the acetylcholine (ACh)-sensitive potassium current in guinea pig type Ⅱ vestibular hair cells. Methods Under the whole-cell patch mode, the current amplitude of the ACh-sensitive potassium current was recorded in response to the concentration change of the extracellular or intracellular Ca^2+. Results Following application of ACh, type II vestibular hair cells displayed the sustained potassium current, which was inhibited by tetraethylammonium chloride (TEA), but not inhibited by 4-aminopyride (4-AP). The activation of the ACh-sensitive potassium current was strongly affected by the concentration of the extracellular Ca^2+ . The current amplitude of the AChsensitive potassium increased following the increase of Ca^2+ concentration from 0 mmol/L to 4 mmol/L. At the concentration of 4 mmol/L Ca^2+ , the current amplitude of the ACh-sensitive potassium current reached the maximal response. Lowering the Ca^2+ concentration in the external solution from 4 mmol/L to 0. 5 mmol/L, the current amplitude of the ACh-sensitive potassium current was inhibited to ( 36. 5 ± 6. 5 ) %. However, no difference was found in the presence and in the absence of the intracellular heparin, which was a well-known blocker of the inositol trisphosphate-dependent calcium release channels. In addition, the calcium channel blocker, Cd^2+ , inhibited the ACh-sensitive potassium current. Conclusions The activation of the ACh- sensitive potassium current in guinea pig type Ⅱ vestibular hair cells was dependent on the extracellular Ca^2+ influx through the calcium channel. The application of ACh would stimulate membrane Ca^2+ channels; the influx of Ca^2+ will then activate the calcium-dependent potassium current in guinea pig type II hair cells to mediate the hyperpolarization effect.
出处 《中华耳鼻咽喉头颈外科杂志》 CAS CSCD 北大核心 2006年第5期369-373,共5页 Chinese Journal of Otorhinolaryngology Head and Neck Surgery
基金 国家杰出青年科学基金资助项目(39925035) 国家自然科学基金资助项目(30070809 30371525) 国家"十五"科技攻关计划(2004BA720A18-02) 2004-2006卫生部临床学科重点项目资助
关键词 毛细胞 前庭 乙酰胆碱 Hair cells,vestibular Acetylcholine Potassium Calcium
  • 相关文献

参考文献3

二级参考文献30

  • 1莫玲燕,苏鸿禧.豚鼠壶腹嵴毛细胞分离法[J].中华耳鼻咽喉科杂志,1993,28(3):131-133. 被引量:4
  • 2[1]Guth PS,Norris CH and Bobbin RP.The pharmacology of transmission in the peripheral auditory system.Pharmacol Rev ,1976,28:15-125.
  • 3[2]Klinke R and Galley N.Efferent innervation of vestibular and auditory receptors.Physiol Rev,1974,54:316-357.
  • 4[3]Kong WJ,Egg G,Hussl B,spoendlin H,Schrott-Fischer A .Localization of chat-like immunoreativity in the vestibular endorgans of the rat.Hear Res,1994,75:191-200.
  • 5[4]Kong WJ,Scholtz AW,Hussl B,Kammen-Jolly K,Schrott-Fischer A.Localization of efferent neurotransmitters in the inner ear of the homozygous Bronx waltzer mutant mouse.Hear Res,2002,167:136-55
  • 6[5]Kong WJ,Hussl B,Thumfart WF,Schrott-Fischer A.Ultrastrucural localization of ChAT-like immunoreactivity in the human vestibular periphery.Hear Res,1998,119:96-103.
  • 7[6]Schrott-Fischer A,Kammen-Jolly K,Scholtz AW,Kong WJ,Eybalin M.Neurotransmission in the human labyrinth.Adv Otorhinolaryngol,2002,59:11-7
  • 8[7]Ishiyama A,Lopel I,Wackym PA.Molecular characterization of muscarinic receptors in the human vestibular periphery:Implications for Pharmactherapy.Am J Otol,1997,18:648-54.
  • 9[8]Hiel H,Elgoyhen AB,Drescher DG,Morley BJ.Expression of nicotinic acethy1choline receptor mRNA in the adult rat peripheral vestibluar system.Brain Res ,1996,38:347-52.
  • 10[9]Scarfone E,Ulfendahl M,Lfstrand P,and Flock A.Light-and electron microscopy of isolated vestibular hair cells from the guinea pig.cell Tissue Res,1991,266:51-58.

共引文献7

同被引文献28

  • 1姚琦,孔维佳,程华茂,吴婷婷,夏交,朱云.N型乙酰胆碱受体α10亚基在大鼠内耳耳蜗及前庭中的表达[J].听力学及言语疾病杂志,2006,14(3):195-197. 被引量:2
  • 2程华茂,孔维佳,姚琦.毒蕈碱样乙酰胆碱受体m1~m5亚基在大鼠前庭终器组织中的表达[J].临床耳鼻咽喉科杂志,2006,20(22):1027-1029. 被引量:1
  • 3Guth IS, Perin P, Norris CH, et al. The vestibular hair cells: post-transductional signal processing. Prog Neurobiol, 1998, 54 : 193 -247.
  • 4Holt JC, Lioudyno M, Athas G, et al. The effect of proteolytic enzymes on the alpha9-nicotinic receptor-mediated response in isolated frog vestibular hair cells. Hear Res, 2001, 152: 25-42.
  • 5Katz E, Verbitsky M, Rothlin CV, et al. High calcium permeability and calcium block of the alpha9 nicotinic acetylcholine receptor. Hear Res, 2000, 141 : 117-128.
  • 6Elgoyhen AB, Vetter DE, Katz E, et al. alpha10: a determinant of nicotinic cholinergic receptor function in mammalian vestibular and cochlear mechanosensory hair cells. Proc Nail Acad Sci USA, 2001, 98: 3501-3506.
  • 7Jagger DJ, Griesinger CB, Rivolta MN, et al. Calcinum signaling mediated by the α9 acetylcholine recetor in a cochlear cell line from the immortomouse. J Physiol, 2000, 527: 49-54.
  • 8Ishiyama A, Lopez I, Wackym PA. Molecular characterization of muscarinic receptors in the human vestibular periphery. Implications for pharmacotherapy. Am J Otol, 1997, 18: 648-654.
  • 9Armstrong CE, Roberts WM. Rapidly inactivating and noninactivating calcium-activated potassium currents in frog saccular hair cells. J Physiol, 2001, 536: 49-65.
  • 10Perin P, Masetto S, Martini M, et al. Regional distribution of calcium currents in frog semicircular canal hair cells. Hear Res, 2001, 152: 67-76.

引证文献2

相关作者

内容加载中请稍等...

相关机构

内容加载中请稍等...

相关主题

内容加载中请稍等...

浏览历史

内容加载中请稍等...
;
使用帮助 返回顶部