M. Nitz et al., Localization of low affinity nerve growth factor receptor in the rat inferior olivary complex during development and plasticity of climbing fibres, DEV BRAIN R, 126(2), 2001, pp. 229-239
The rat olivocerebellar pathway has a precise topography from an inferior o
live (TOC) to Purkinje cells in the contralateral hemicerebellum. While its
development and plasticity have been documented, the molecular mechanisms
underlying these events are not fully elucidated. Neurotrophins are a famil
y of growth factors with diverse roles in development and neuronal plastici
ty, acting through a two-receptor system, including a low affinity receptor
(LNGFR) which binds all neurotrophins with similar affinity. Since neurotr
ophins are present in the cerebellum during early postnatal development whe
n LNGFR is synthesized in the IOC, they may act as target-derived trophic a
gents for climbing fibres during development and plasticity. To assess this
, standard immunohistochemistry was used to document the distribution of LN
GFR in the rat. IOC during climbing fibre development and until cerebellar
development was complete at postnatal day 28 (P28). LNGFR immunoreactivity
(LNGFR-IR) was detected in the IOC from P0 until P15, however after P7 it d
iminished in intensity and distribution, a change which indicates a relatio
nship between cerebellar neurotrophins and climbing fibre development. Afte
r denervation of the left hemicerebellum, there was an apparent increase in
inferior olivary LNGFR-IR that was concurrent with climbing fibre re-inner
vation. Thus the results of this study support the hypothesis that neuroutr
ophins are involved in climbing fibre development and suggest a possible co
ntribution to the plasticity of the olivocerebellar pathway. (C) 2001 Elsev
ier Science B.V. All rights reserved.