Abstract
Abstract: :
Purpose:To profile changes in inducible transcription factors expression after retinal ischemia reperfusion injury, using gene microarray analysis and immunohistochemical study. Methods:Retinal ischemia were created by increasing the intraocular pressure to 110 mm Hg for 1 hour in adult rats. At 12 hours after reperfusion, rat retinas were isolated from ischemic and non-ischemic eyes. Poly(A) RNA was prepared from the retinas. Double-stranded cDNA was synthesized from the poly(A) RNA with an oligo-dT primer containing a T7 RNA polymerase promoter sequence at the 3'-end. Biotin-labeled antisense cRNA as a probe of microarray analysis was produced by in vitro transcription reaction. The cRNA was hybridized with Affymetrix RATU34A oligonucleotide microarrays. The microarray contained approximately 8,800 of rat cDNA clones including EST clones. Paraffin embedded retinal sections were prepared for immunohistochemistry. Results:Fluorescence intensity was measured for each chip and normalized to the average fluorescence intensity for the entire chip. The values were compared between the ischemic retina and the non-ischemic retina. Expression changes of 262 clones are increased or decreased an average of 2.1-fold and more in the ischemic retina. Some transcriptional regulatory genes (jun-and fos-related protein) are upregulated at 4- to 44-fold. Immunohistochemical studies showed that expression of transcriptional regulatory gene products were upregulated in dying neurons and/or surrounding glial cells. Conclusion:This study suggests that increased expression of transcriptional regulatory proteins play a role in retinal neuronal apoptosis after ischemia-reperfusion injury.
Keywords: 323 apoptosis/cell death • 605 transcription factors • 448 ischemia