CNTF promotes the regrowth of retinal ganglion cell axons into murine peripheral nerve grafts

Autologous peripheral nerves were transplanted onto transected optic nerves of adult mice. We examined whether intraocular CNTF injections increased retinal ganglion cell (RGC) axon regeneration, and what types of RGCs regrew axons into grafts. After temporal CNTF eye injections there were more fluorogold-labelled regenerating RGCs (mean +/- s.e.m. 342 +/- 113.1; n = 6) than in sham eye-injected mice (133 +/- 27.6; n = 8). Greater numbers of regenerating RGCs (1198 +/- 367.6; n = 6) were seen in mice receiving both nasal and temporal CNTF injections. The range of soma areas in regenerate and normal retinas was similar but the average size of regenerating RGCs was greater (212 mum(2) vs 111 mum(2)). Most regenerating RGCs had large dendritic fields. The data suggest RGCs preferentially regrowing axons into PN grafts. NeuroReport 11:3999-4002 (C) 2000 Lippincott Williams & Wilkins.