Neurotrophic factors promoting the expression of retinal growth associated protein-43 in retina after crush injuries of the optic nerve

ObjectiveTo observe the growth associated protein-43 ( GAP-43 ) expression in the rat retina after injuries of the optic nerve, and the protection of the optic nerve with ciliary neurotrophic factor ( CNTF ) and adenovirally delivered brain-derived neurotrophic factor ( Ad-BDNF).MethodsThe optic nerve were crushed 2mm behind the eye ball of SD rats. The neurothophic factors ( NFs ) were intravitreal injected immediately after optic nerve crush. The expression of GAP-43 in the rat retina was observed by western-blot analysis. ResultsThere was low GAP-43 expression in normal SD rat retina, and the molecular weight was about 46.7ku. Intravitreal injection of CNTF after optic nerve crush could promote the expression of GAP-43 in rats retina in 2 weeks (P0 05 ).Meanwhile intravitreal injection of Ad-BDNF after optic nerve crush could promote the expression of GAP-43 in rats retina in 4 weeks (P0.05 ). But this promoting effect was more obvious 1 week after crush.ConclusionIntravitreal injection of NFs could promote the expression of GAP-43 in rat retina after optic nerve crush. But this effect is time-limited, and the Ad-BDNT could promote it for a longer time.