Nishiyama Hiroshi, Fukaya Masahiro, Watanabe Masahiko, Linden David J
Department of Neuroscience, The Johns Hopkins University School of Medicine, 725 N. Wolfe Street, Baltimore, MD 21205, USA.
Neuron. 2007 Nov 8;56(3):472-87. doi: 10.1016/j.neuron.2007.09.010.
We performed two-photon in vivo imaging of cerebellar climbing fibers (CFs; the terminal arbor of olivocerebellar axons) in adult mice. CF ascending branches innervate Purkinje cells while CF transverse branches show a near complete failure to form conventional synapses. Time-lapse imaging over hours or days revealed that ascending branches were very stable. However, transverse branches were highly dynamic, exhibiting rapid elongation and retraction and varicosity turnover. Thus, different branches of the same axon, with different innervation patterns, display branch type-specific motility in the adult cerebellum. Furthermore, dynamic changes in transverse branch length were almost completely suppressed by pharmacological stimulation of olivary firing.
我们对成年小鼠的小脑攀缘纤维(CFs;橄榄小脑轴突的终末分支)进行了双光子活体成像。CF的上升分支支配浦肯野细胞,而CF的横向分支几乎完全无法形成传统突触。数小时或数天的延时成像显示上升分支非常稳定。然而,横向分支具有高度动态性,表现出快速的伸长和回缩以及膨体更新。因此,同一轴突的不同分支,具有不同的支配模式,在成年小脑中表现出分支类型特异性的运动性。此外,通过药理学刺激橄榄体放电,横向分支长度的动态变化几乎完全受到抑制。