Intrinsic properties of mouse lumbar motoneurons revealed by intracellular recording in vivo
作者单位：Department of Neuroscience and PharmacologyUniversity of CopenhagenPanum InstituteBlegdamsvej 3DK-2200 Copenhagen NDenmark Department of Sports ScienceUniversity of CopenhagenPanum InstituteBlegdamsvej 3DK-2200 Copenhagen NDenmark Departmentof Neuroscience and PharmacologyUniversity of CopenhagenPanum InstituteBlegdamsvej 3DK-2200 Copenhagen NDenmark
会议名称：《中国神经科学学会第四次会员代表大会暨第八届全国学术会议》
会议日期：2009年
学科分类：0710[理学-生物学] 07[理学] 071006[理学-神经生物学]
关 键 词：motoneurons mouse
摘 要：正As a basis for investigations on motoneurone properties in various transgenic mouse strains we here describe basic electrophysiological properties of mouse hindlimb -motoneurones（MNs） in an adult in vivo *** particular aim of the present study is to evaluate to which extent the properties controlling the firing frequency are tailored to the characteristics of the mouse muscle contraction *** mice of the C57BL strain were anaesthetized using a cocktail of fentanyl（Hypnorm） and ***-one motoneurones with antidromic spike potentials（ 50 mV） from the sciatic nerve were included in this *** mean input resistance（RIN） was 2.4±1.2（SD） MΩ;and the mean rheobase 6.7±5.4（SD） *** mean duration from the start of a spike to the time at which the afterhyperpolarization（AHP） had returned by 2/3 towards the baseline（AHP2/3） was 21.7±6.0（SD） *** on this;the estimated return of the AHP to baseline（AHPd） was 55.3±14（SD） *** minimum firing frequency（Fmin） and maximum firing frequencies（Fmax） at steady firing were 20.8 Hz and 300 Hz respectively（reaching as high at 400 Hz）.The mean slope of the currentfrequency relation（f/I-slope） with increasing amounts of current injected was 13±5.7（SD） Hz/*** of activation of persistent inward currents（PICs）,such as accelerations of firing frequency or jumps in the membrane potential,were seen with increasing amounts of injected *** the ascending and descending phases of triangular current injections demonstrated a counter-clockwise hysteresis as has been previously described in the cat and the *** presence of the voltage gated calcium channel,Cav 1.3,which mediates PICs,was also demonstrated immunohistochemically. These results prove that it is feasible to obtain in vivo recordings from the adult mouse,thus paving the way for subsequent experiments in transgenic *** present data demonstrate that mouse spinal motoneurones share many of the same propertie