Upregulation of ciliary neurotrophic factor in reactive Muller cells in the rat retina following optic nerve transection

We have investigated the expression and cellular localization of ciliary ne urotrophic factor (CNTF) in the rat retina following optic nerve transectio n. In the normal retina, CNTF immunoreactivity was restricted to profiles i n the ganglion cell layer. Following optic nerve transection, immunoreactiv ity appeared in Muller cell somata and processes and its intensity increase d between three and seven days post-lesion. Quantitative evaluation by immu noblotting confirmed that CNTF expression increased continuously up to 7 da ys after optic nerve transection (to 430% of control levels), but decreased again to 250% of controls at 4 weeks post-lesion. Our findings suggest tha t CNTF supplied by Muller cells may play a protective role for axotomized g anglion cells in the rat retina. (C) 2000 Elsevier Science B.V. All rights reserved.