Microarray Analysis Of Genes Expressed By Retinal Microvascular Cells In Early Diabetic Rats

Our knowledge about the pathogenesis of early diabetic retinopathy has expanded dramatically in the recent years. Diabetic retinopathy is no longer viewed as a microvascular complication alone. Diabetic retinopathy affects all cell types in retina producing retinal neuropathy as well as microangiopathy. Diabetic retinopathy also possesses significant inflammatory components. Accelerated apoptosis is evident in both vascular and neuronal cells within retina. Therefore, the comprehensive gene profiles of retinal cells, particularly vascular cells, have been studied by high throughput of microarray technique with diabetic animals.Sprague-Dawley male rats were induced to diabetes by intraperitoneal injection of streptozotocin. Hyperglycemia was monitored and the morphologic changes of retinal vessels were examined at the designed intervals. The rats were scarified at 3, 6 and 9 weeks after the induction of diabetes. 12 to 18 retinas were pooled and retinal microvessels (MV) were then purified for total RNA isolation. Nylon slides containing 1176 genes were hybridized to ³²P-dCTP-labeled cDNA that were synthesized using total RNAs. The purity of enriched retinal MV was proved by interference microscopy. 0. 5 to 1 ug total RNA were extracted from 12 to 18 retinal MV preparations. Of the 1176 genes on the nylon slides, 12.5%, 13. 44%and 8.25% genes were differentially expressed (up-regulated or down-regulated more than twofold in the diabetes...