Figure 2. Effect of diabetes on expression of NMDA receptor subunits. qRT-PCR analysis was performed on cDNA isolated from control and STZ-induced diabetic rat retina after 4 and 12 weeks. Expression of each gene was normalized to acidic ribosomal phosphoprotein (P0) for each rat (A), and then scaled to the 4-week control rats for each gene (B; mean ± SEM). Compared to the age-matched control rats, the 12-week diabetic rats had significantly reduced transcript levels of GRIN1, GRIN2A, GRIN2B, and GRIN2D (*, p<0.05; **, p<0.01; *** p<0.005). Transcript levels of GRIN2C were significantly increased in the 4-week diabetic rats compared to the age-matched control rats (*, p<0.05).