Investigative ophthalmology & visual science
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Invest. Ophthalmol. Vis. Sci. · May 2005
Time course of neurotrophic factor upregulation and retinal protection against light-induced damage after optic nerve section.
To assess neurotrophic factor upregulation in the retina after damage to the optic nerve and relate that regulation to changes in photoreceptor stability and function. ⋯ The upregulation of CNTF 7 to 14 days after nerve section correlates with a reduction in the a-wave described previously. Colocalization of CNTF and CNTFRalpha on the outer segments suggests that CNTF acts at the photoreceptor membrane. The slower upregulation of FGF-2 correlates with a reduction of the b-wave. FGF-2/FGFR1 colocalization in the OPL suggests that this factor acts at the synaptic terminals of photoreceptors, modulating the release of neurotransmitters. The time course of pERK upregulation suggests that the successive upregulation of CNTF and FGF-2 activates the ERK pathway. Based on the time course of protection against bright continuous light, it seems that CNTF plays a major role in this effect, and FGF-2 has a less important role in the protection against light-induced damage.