Figure 5.

Effect of AGE treatment on iNOS expression and NO production in islets. Isolated islets were treated with BSA or AGE-BSA for 48 h. A, Total RNA was isolated for determination of iNOS and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA levels by RT-PCR and 1% agarose electrophoresis, and the ratio of iNOS vs. glyceraldehyde-3-phosphate dehydrogenase was plotted. B, Islet cell lysates were prepared for Western blot analysis of iNOS and β-actin expression, and the ratio of iNOS vs. β-actin was plotted. C, Nitrite levels in islet-cultured media were measured using Griess reagent (modified). Data are presented as means ± sem of three independent experiments. *, P < 0.01 compared with control.