Abstract
Abstract: :
Purpose: The rd mouse retina is characterized by selective degeneration of rod photoreceptors during the first month in vivo or in organ culture. We have previously shown that the trophic factors ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF) added in combination to rd mouse retinal organ cultures block photoreceptor cell death. Here we investigate the effects of CNTF and/or BDNF on photoreceptor-associated proteins in organ culture. Methods: Retinas were harvested from rd or wild type control mice at postnatal day 2 and grown in organ culture for 4 weeks in DMEM with 10% fetal calf serum. Cultures were treated with CNTF and/or BDNF. Tissue was fixed, processed, and cryosectioned for immunohistochemistry. Results: CNTF and BDNF in combination block photoreceptor degeneration in rd organ cultures and suppress rhodopsin-like immunoreactivity (LIR). CNTF alone does not inhibit photoreceptor degeneration in organ culture, but does suppress rhodopsin-LIR. BDNF alone also does not inhibit photoreceptor degeneration in organ culture; it has no effect on rhodopsin-LIR. Immunoreactivity for the transcription factor CRX was not altered by either trophic factor. Conclusion: These findings suggest that CNTF's role in blocking photoreceptor degeneration in the rd mouse organ culture may involve inhibition of rod specific protein expression. However, CNTF alone does not block photoreceptor degeneration in this model. Further investigation of the role of BDNF is needed.
Keywords: 423 growth factors/growth factor receptors • 561 retinal degenerations: cell biology • 517 photoreceptors