神經(jīng)組織-神經(jīng)纖維（組織胚胎學(xué)）

神經(jīng)纖維目錄CONTENT01有髓神經(jīng)纖維02無髓神經(jīng)纖維03神經(jīng)03神經(jīng)纖維概述組成：神經(jīng)元的長軸突及包繞它的神經(jīng)膠質(zhì)細(xì)胞神經(jīng)纖維概述01分類：有髓神經(jīng)纖維（形成髓鞘）無髓神經(jīng)纖維（無髓鞘）分布：白質(zhì)以及腦脊神經(jīng)、自主神經(jīng)有髓神經(jīng)纖維無髓神經(jīng)纖維神經(jīng)纖維掃描電鏡圖（偽彩）紫色部分為軸突；灰色為神經(jīng)膠質(zhì)細(xì)胞施萬細(xì)胞呈長卷筒狀套在軸突外郎飛結(jié)：相鄰施萬細(xì)胞間的狹窄處相鄰結(jié)間體：兩個(gè)郎飛結(jié)間的一段神經(jīng)纖維，一個(gè)結(jié)間體的外圍部分即為一個(gè)施萬細(xì)胞施萬細(xì)胞的結(jié)構(gòu)：髓鞘有髓神經(jīng)纖維02周圍神經(jīng)系統(tǒng)有髓神經(jīng)纖維外側(cè)胞質(zhì)髓鞘內(nèi)側(cè)胞質(zhì)郎飛結(jié)結(jié)間體施萬細(xì)胞軸突髓鞘髓鞘成分：髓磷脂和蛋白質(zhì)髓鞘形態(tài)：LMHE染色—網(wǎng)狀

鋨酸染色—黑色，可見髓鞘切跡EM明暗相間的同心圓板層狀髓鞘形成：由施萬細(xì)胞的細(xì)胞膜同心卷繞多層形成髓鞘切跡周圍神經(jīng)纖維髓鞘形成及髓鞘橫切面掃描電鏡圖Ax：軸突；Ms：髓鞘；Sc：外側(cè)胞質(zhì)中樞神經(jīng)系統(tǒng)有髓神經(jīng)纖維結(jié)構(gòu)：與周圍神經(jīng)系統(tǒng)的有髓神經(jīng)纖維基本相同，但是由少突膠質(zhì)細(xì)胞形成髓鞘少突膠質(zhì)細(xì)胞神經(jīng)纖維軸突髓鞘郎飛結(jié)少突膠質(zhì)細(xì)胞的多個(gè)突起末端形成扁平薄膜，可包卷多個(gè)軸突，其胞體位于神經(jīng)纖維之間神經(jīng)纖維外表面無基膜，髓鞘內(nèi)無切跡無髓神經(jīng)纖維02周圍神經(jīng)系統(tǒng)由軸突和神經(jīng)膜細(xì)胞構(gòu)成無髓鞘，無郎飛結(jié)一個(gè)神經(jīng)膜細(xì)胞可包裹多條軸突中樞神經(jīng)系統(tǒng)軸突裸露，軸突外無任何鞘膜與有髓神經(jīng)纖維混雜施萬細(xì)胞軸突施萬細(xì)胞軸突周圍神經(jīng)系統(tǒng)無髓神經(jīng)纖維神經(jīng)纖維功能傳導(dǎo)神經(jīng)沖動有髓神經(jīng)纖維的神經(jīng)沖動在郎飛結(jié)間呈跳躍式傳導(dǎo)，故傳導(dǎo)速度快無髓神經(jīng)纖維的神經(jīng)沖動沿軸膜連續(xù)傳導(dǎo)，故傳導(dǎo)速度慢脊神經(jīng)血管神經(jīng)外膜神經(jīng)束膜神經(jīng)內(nèi)膜神經(jīng)03周圍神經(jīng)系統(tǒng)的神經(jīng)纖維集合在一起，構(gòu)成神經(jīng)，分布到全身各器官多數(shù)神經(jīng)兼含感覺神經(jīng)纖維、運(yùn)動神經(jīng)纖維及自主神經(jīng)纖維神經(jīng)內(nèi)膜神經(jīng)纖維外周神經(jīng)橫切面掃描電鏡圖外周神經(jīng)橫切面光鏡圖小結(jié)神經(jīng)纖維由神經(jīng)元長軸突以及包繞它的神經(jīng)膠質(zhì)細(xì)胞構(gòu)成。分為有髓神經(jīng)纖維和無髓神經(jīng)纖維兩類。有髓神經(jīng)纖維的髓鞘是由施萬細(xì)胞或少突膠