单侧迷路破坏后大鼠前庭神经内侧核区氨基酸含量的变化VIP免费

71ActaPhysiologicaSinica,February25,2007,59(1):71-78http://www.actaps.com.cnResearchPaperReceived2006-07-03Accepted2006-12-14ThisworkwassupportedbytheProminentYouthfulScienceFoundationofJilinProvince(No.20040109).*Correspondingauthor.Tel:+86-433-2660586;E-mail:y-z-jin@ybu.edu.cnChangesofaminoacidconcentrationsintheratmedialvestibularnucleusfollowingunilaterallabyrinthectomyYUHai-Ling1,ANYing2,JIANGHai-Ying2,JINQing-Hua2,JINYuan-Zhe2,*1DepartmentofPharmacology;2DepartmentofPhysiology,YanbianUniversityCollegeofMedicine,KeyLaboratoryofOrganismFunctionalFactorsoftheChangbaiMountain,MinistryofEducation,Yanji133000,ChinaAbstract:Tounderstandtheneurochemicalmechanismsunderlyingthevestibularcompensation,wedeterminedthelevelsofaminoacidssuchasaspartate,glutamate,glutamine,glycine,taurine,alanineinthemedialvestibularnucleus(MVN)followingunilaterallabyrinthectomy(UL),byusinginvivobrainmicrodialysisandhigh-performanceliquidchromatographytechnique.Ratswerepre-treatedbyinfusing2%lidocaine1.2mLor10mgarsanilicacidintothetympaniccavitytoobstructuni-peripheryvestibularorgan,andthenthelevelsofaminoacidsweredeterminedinMVNofnormalcontrolandipsilateralorcontralaterallesional(ipsi-/contra-lesional)rats.Inthecontrolexperiment,thelevelsofaspartate,glutamate,glutamine,glycine,taurine,andalaninewere(6.15±0.59),(18.13±1.21),(33.73±1.67),(9.26±0.65),(9.56±0.77)and(10.07±0.83)pmol/8µLsample,respectively.Theconcentrationsofaspartateandglutamatedecreased,whiletheconcentrationoftaurineincreasedintheipsi-lesionalMVNofrats10minafterinfusing2%lidocaineintomiddleeartoobstructuni-peripheryvestibularorgan.Whereastheconcentrationofglutamateincreased,theconcentrationsofglycineandalaninedecreasedinthecontra-lesionalMVN,accompaniedbyimbalancesofglutamate,glycineandalanineinthebilateralnuclei.Incontrast,thelevelsofglutamateandalaninedecreased,thelevelofglutamineincreasedintheipsi-lesionalMVN,andthelevelofglutamatedecreasedinthecontra-lesionalMVNofrats2weeksafterinfusing10mgarsanilicacidintothetympaniccavitytoobstructuni-peripheryvestibularorgan.Furthermore,thelevelofglutamineintheipsi-lesionalMVNwasobviouslyhigherthanthatinthecontra-lesionalMVN.TheseresultsdemonstratethatanimbalanceofdifferentaminoacidsappearedinbilateralMVNafterUL,andthisimbalancedecreasedafterthedevelopmentofvestibularcompensation.Whereastheimbalanceofglutaminereleaseinbilateralnucleiappearedaftervestibularcompensation.Keywords:aminoacids;medialvestibularnucleus;unilaterallabyrinthectomy;vestibularcompensation单侧迷路破坏后大鼠前庭神经内侧核区氨基酸含量的变化于海玲1，安英2，姜海英2，金清华2，金元哲2,*延边大学医学院1药理学教研室；2生理学教研室，长白山生物功能因子省部共建教育部重点实验室，延吉133000摘要：本实验用脑部微量透析法和高效液相色谱法观察单侧迷路破坏(unilaterallabyrinthectomy，经利多卡因或对氨基苯胂酸盐预处理以阻断单侧外周前庭器官)后大鼠同侧及对侧前庭神经内侧核(medialvestibularnucleus,MVN)区部分氨基酸(天冬氨酸、谷氨酸、谷氨酰胺、甘氨酸、牛磺酸和丙氨酸)含量的变化，以了解前庭代偿的部分神经化学机制。实验观察到，对照组大鼠MVN区天冬氨酸、谷氨酸、谷氨酰胺、甘氨酸、牛磺酸和丙氨酸浓度分别为(6.15±0.59)，(18.13±1.21)，(33.73±1.67)，(9.26±0.65)，(9.56±0.77)和(10.07±0.83)pmol/8µL透析样本。左侧中耳内灌注2%利多卡因后10min，同侧MVN区天冬氨酸、谷氨酸含量立即减少(P<0.05)，牛磺酸含量增加(P<0.05)；对侧MVN区谷氨酸含量立即增加(P<0.05)，甘氨酸和...