水杨酸钠与细胞外钾离子对豚鼠单离外毛细胞外向钾电流和静息电位的影响  

Effects of sodium salicylate and extracellular K^+ on outward potassium current and resting potential of outer hair cell isolated from guinea pig cochlea

作　　者：梁勇[1] 钟乃川[2] 

机构地区：[1]第一军医大学南方医院耳鼻咽喉科,广东广州510515 [2]华中科技大学同济医学院协和医院耳鼻咽喉科,湖北武汉430022

出　　处：《第一军医大学学报》2002年第2期137-140,共4页Journal of First Military Medical University

摘　　要：摘要:目的探讨单独使用水杨酸钠或在细胞外液中先加入氯化钾再加入水杨酸钠后,豚鼠单离外毛细胞(OHC)钾电流(IK)和静息电位(RP)的变化,分析水杨酸钠和K+对OHC生理功能影响的特点及其相互关系。方法应用膜片钳全细胞记录技术,测试单独使用1mmol/L水杨酸钠以及在细胞外液中先加入10mmol/L氯化钾再加入1mmol/L水杨酸钠后IK和RP的变化。结果水杨酸钠具有使IK先增加后降低的双相时-效药理作用;细胞外液中加入氯化钾后,水杨酸钠对IK的作用减弱。水杨酸钠有降低RP的作用,但时-效关系不明显;细胞外液中加入氯化钾后,RP升高,然后回降至用药前水平。结论水杨酸钠对OHC生理功能的影响与K+有关,可影响OHC侧膜的K+电导和细胞内外K+分布,并通过对IK和RP的影响而改变OHC的兴奋性和机械活动特性,这些作用有可能是水杨酸影响OHC功能的耳蜗机制之一。Objective To investigatetheeffectsof sodiumsalicylateandextracellularK + on thefunctionsof outerhaircells(OHCs)and the relationsbetweentheiractions.Methods Sodiumsalicylateat the concentrationof1mmol/Lwas administeredeitheraloneor following10mmol/LKCl intothe extracellularsolutionof OHCsisolatedfromguineapig cochlea.Theoutwardpotassiumcurrent(I K )andrestingpotential(RP)of OHCswas measuredusingpatch-clampwholecell recordingtechnique.Results Time-dependentchangesin theeffectof sodiumsalicylateon I K was observed,namely,I K underwenttransientincreaseandthendeclinedaftersodiumsalicylateadministration.WhenKClwasadministeredpreviously intothe extracellularsolution,theeffectof sodiumsalicylateon I K was reduced.SodiumsalicylatecoulddecreaseRPbutnot time-dependentlyintheabsenceof KCl,andwhenpriorKCltreatmentwas administered,onlytemporaryincreaseinRPtook placebeforeRPreturnedto thelevelbeforesodiumsalicylateadministration.Conclusions Theeffectsof sodiumsalicylateon OHCfunctionswererelatedto K + ,andtheformeragentmayaffectK + conductionandinternalandexternaldistributionof K + inOHCs,andcausesthe changesintheexcitabilityandmechanicalactivityof OHCsby meansof affectingI K andRP.This hypothesismightbe oneof thecochlearmechanismsby whichsodiumsalicylateaffectsOHCfunctions.

关 键 词：水杨酸钠 膜电位 外毛细胞 耳毒性 外通道 

分 类 号：R339.174[医药卫生—人体生理学]