Figure 4
Increased D-serine and glutamate in aqueous humor of DR rats determined by HPLC. A: Amino acid standards were separated by reverse-phase HPLC; 1: L-Asp, TR = 9.243 min; 2: L-Glu, TR = 12.995 min; 3: L-Ser, TR = 19.472 min; 4: L-Gln, TR = 20.108 min; 5: D-Ser, TR = 21.302 min. B, C: Aqueous humor samples from control rats (B) or from DR rats (C) at 3 months after onset of diabetes. D: Quantification of glutamate and D-serine in aqueous humor from DR and control rats at 3 months after onset of diabetes. E: Quantification of glutamate and D-serine in aqueous humor from DR and control rats at 5 months after onset of diabetes. The results shown are mean ± SEM from triplicate experiments (*P < 0.05 vs. control).