神经损伤与功能重建
神經損傷與功能重建
신경손상여공능중건
NEURAL INJURY AND FUNCTIONAL RECONSTRUCTION
2010年
3期
189-203
,共15页
少突胶质细胞%缝隙连接%星形胶质细胞%钾%髓鞘%NG2%Olig2
少突膠質細胞%縫隙連接%星形膠質細胞%鉀%髓鞘%NG2%Olig2
소돌효질세포%봉극련접%성형효질세포%갑%수초%NG2%Olig2
oligodendrocyte%gap junction%astrocyte%potassium (K+)%myelin%NG2%Olig2%ion channe
已有的超微结构研究显示,白质中的少突胶质细胞和星形胶质细胞之间存在缝隙连接,但少突胶质细胞之间不存在缝隙连接,虽然体外培养的少突胶质细胞可形成功能性缝隙连接.本文研究新生小鼠胼胝体急性脑片中的少突胶质细胞的功能性连接.以全细胞膜片钳技术用生物胞素(一种可渗透的缝隙连接示踪剂)标记少突胶质细胞.平均61个细胞为链霉亲和素-Cy3标记的生物胞素阳性.约77%的连结细胞表达少突胶质细胞标志蛋白CNPase阳性染色,9%表达星形胶质细胞标志蛋白GFAP阳性,14%为CNPase和GFAP阴性.后者的大部分表达Olig2和一些NG2(少突胶质细胞前体细胞的标志物).少突胶质细胞表达Cx47、Cx32和Cx29,星形胶质细胞表达Cx43和Cx30.在Cx47敲除小鼠中,连结细胞的数量减少80%.单独删除Cx32或Cx29并不能显著减少连结细胞的数量,但Cx32/Cx47双缺陷小鼠中没有观察到相互连结的细胞.Cx47敲除完全消除了少突胶质细胞与星形胶质细胞间的耦联.在Cx43敲除动物中,少突胶质细胞-星形胶质细胞间连接仍然存在,但与少突胶质细胞前体细胞间的耦联没有被观察到.在Cx43/Cx30双敲除小鼠中,少突胶质细胞-星形胶质细胞连接几乎不存在.解开连结的少突胶质细胞显示为较高的膜输入电阻.本文认为,白质中的少突胶质细胞依靠Cx47和Cx32的表达形成功能性的合胞体,而星形胶质蛋白缝隙连接蛋白的表达能提升此网络的大小.
已有的超微結構研究顯示,白質中的少突膠質細胞和星形膠質細胞之間存在縫隙連接,但少突膠質細胞之間不存在縫隙連接,雖然體外培養的少突膠質細胞可形成功能性縫隙連接.本文研究新生小鼠胼胝體急性腦片中的少突膠質細胞的功能性連接.以全細胞膜片鉗技術用生物胞素(一種可滲透的縫隙連接示蹤劑)標記少突膠質細胞.平均61箇細胞為鏈黴親和素-Cy3標記的生物胞素暘性.約77%的連結細胞錶達少突膠質細胞標誌蛋白CNPase暘性染色,9%錶達星形膠質細胞標誌蛋白GFAP暘性,14%為CNPase和GFAP陰性.後者的大部分錶達Olig2和一些NG2(少突膠質細胞前體細胞的標誌物).少突膠質細胞錶達Cx47、Cx32和Cx29,星形膠質細胞錶達Cx43和Cx30.在Cx47敲除小鼠中,連結細胞的數量減少80%.單獨刪除Cx32或Cx29併不能顯著減少連結細胞的數量,但Cx32/Cx47雙缺陷小鼠中沒有觀察到相互連結的細胞.Cx47敲除完全消除瞭少突膠質細胞與星形膠質細胞間的耦聯.在Cx43敲除動物中,少突膠質細胞-星形膠質細胞間連接仍然存在,但與少突膠質細胞前體細胞間的耦聯沒有被觀察到.在Cx43/Cx30雙敲除小鼠中,少突膠質細胞-星形膠質細胞連接幾乎不存在.解開連結的少突膠質細胞顯示為較高的膜輸入電阻.本文認為,白質中的少突膠質細胞依靠Cx47和Cx32的錶達形成功能性的閤胞體,而星形膠質蛋白縫隙連接蛋白的錶達能提升此網絡的大小.
이유적초미결구연구현시,백질중적소돌효질세포화성형효질세포지간존재봉극련접,단소돌효질세포지간불존재봉극련접,수연체외배양적소돌효질세포가형성공능성봉극련접.본문연구신생소서변지체급성뇌편중적소돌효질세포적공능성련접.이전세포막편겸기술용생물포소(일충가삼투적봉극련접시종제)표기소돌효질세포.평균61개세포위련매친화소-Cy3표기적생물포소양성.약77%적련결세포표체소돌효질세포표지단백CNPase양성염색,9%표체성형효질세포표지단백GFAP양성,14%위CNPase화GFAP음성.후자적대부분표체Olig2화일사NG2(소돌효질세포전체세포적표지물).소돌효질세포표체Cx47、Cx32화Cx29,성형효질세포표체Cx43화Cx30.재Cx47고제소서중,련결세포적수량감소80%.단독산제Cx32혹Cx29병불능현저감소련결세포적수량,단Cx32/Cx47쌍결함소서중몰유관찰도상호련결적세포.Cx47고제완전소제료소돌효질세포여성형효질세포간적우련.재Cx43고제동물중,소돌효질세포-성형효질세포간련접잉연존재,단여소돌효질세포전체세포간적우련몰유피관찰도.재Cx43/Cx30쌍고제소서중,소돌효질세포-성형효질세포련접궤호불존재.해개련결적소돌효질세포현시위교고적막수입전조.본문인위,백질중적소돌효질세포의고Cx47화Cx32적표체형성공능성적합포체,이성형효질단백봉극련접단백적표체능제승차망락적대소.
According to previously published ultrastructural studies,oligodendrocytes in white matter exhibit gap junctions with astrocytes, but not among each other, while in vitro oligodendrocytes form functional gap junctions. We have studied functional coupling among oligodendrocytes in acute slices of postnatal mouse corpus callosum. By whole-cell patch clamp we dialyzed oligodendrocytes with biocytin, a gap junction-permeable tracer. On average 61 cells were positive for biocytin detected by labeling with streptavidin-Cy3. About 77% of the coupled cells stained positively for the oligodendrocyte marker protein CNPase, 9% for the astrocyte marker GFAP and 14% were negative for both CNPase and GFAP. In the latter population, the majority expressed Olig2 and some NG2, markers for oligodendrocyte precursors. Oligodendrocytes are known to express Cx47, Cx32 and Cx29, astrocytes Cx43 and Cx30. In Cx47-deficient mice, the number of coupled cells was reduced by 80%. Deletion of Cx32 or Cx29 alone did not significantly reduce the number of coupled cells, but coupling was absent in Cx32/Cx47-double-deficient mice. Cx47-ablation completely abolished coupling of oligodendrocytes to astrocytes. In Cx43-deficient animals, oligodendrocyte-astrocyte coupling was still present, but coupling to oligodendrocyte precursors was not observed. In Cx43/Cx30-double deficient mice, oligodendrocyte-to-astrocyte coupling was almost absent. Uncoupled oligodendrocytes showed a higher input resistance. We conclude that oligodendrocytes in white matter form a functional syncytium predominantly among each other dependent on Cx47 and Cx32 expression, while astrocytic connexins expression can promote the size of this network. 2010Wiley-Liss,Inc.
