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Abstract #16809 Published in IGR 9-1
Retinal ischemic injury rescued by sodium 4-phenylbutyrate in a rat model
Jeng YY; Lin NT; Chang PH; Huang YP; Pang VF; Liu CH; Lin CTExperimental Eye Research 2007; 84: 486-492
Retinal ischemia is a common cause of visual impairment for humans and animals. Herein, the neuroprotective effects of phenylbutyrate (PBA) upon retinal ischemic injury were investigated using a rat model. Retinal ganglion cells (RGCs) were retrograde labeled with the fluorescent tracer fluorogold (FG) applied to the superior collicoli of test Sprague-Dawley rats. High intraocular pressure and retinal ischemia were induced seven days subsequent to such FG labeling. A dose of either 100 or 400 mg/kg PBA was administered intraperitoneally to test rats at two time points, namely 30min prior to the induction of retinal ischemia and 1h subsequent to the cessation of the procedure inducing retinal ischemia. The test-rat retinas were collected seven days subsequent to the induction of retinal ischemia, and densities of surviving RGCs were estimated by counting FG-labeled RGCs within the retina. Histological analysis revealed that ischemic injury caused the loss of retinal RGCs and a net decrease in retinal thickness. For PBA-treated groups, almost 100% of the RGCs were preserved by a pre-ischemia treatment with PBA (at a dose of either 100 or 400 mg/kg), while post-ischemia treatment of RGCs with PBA did not lead to the preservation of RGCs from ischemic injury by PBA as determined by the counting of whole-mount retinas. Pre-ischemia treatment of RGCs with PBA (at a dose of either 100 or 400 mg/kg) significantly reduced the level of ischemia-associated loss of thickness of the total retina, especially the inner retina, and the inner plexiform layer of retina. Besides, PBA treatment significantly reduced the ischemia-induced loss of cells in the ganglion-cell layer of the retina. Taken together, these results suggest that PBA demonstrates a marked neuroprotective effect upon high intraocular pressure-induced retinal ischemia when the PBA is administered prior to ischemia induction.
Dr. Y.Y. Jeng, Graduate Institute of Veterinary Medicine, College of Bio-resources and Agriculture, National Taiwan University, Taipei, Taiwan
Classification:
5.1 Rodent (Part of: 5 Experimental glaucoma; animal models)
2.13 Retina and retinal nerve fibre layer (Part of: 2 Anatomical structures in glaucoma)
11.8 Neuroprotection (Part of: 11 Medical treatment)