Abstract: Objective To analysis the effect of glucose degradation products (GDPs) on aquaporin-1(AQP1) and endothelial nitric oxide synthase (eNOS) expression in cultured endothelial cells. Methods Endothelial cell line (t End.1) was incubated for 24 hours with two relevant GDPs - methylglyoxal (MGly) or 2-furaldehyde (Fur) at the concentrations reported in traditional peritoneal dialysis fluid (Fur 0.8 μM; MGly 35 μM). AQP1 and eNOS gene expression was detected by reverse transcription-polymerase chain reaction (RT-PCR). AQP1 protein was detected by western blot. Moreover, the effect of GDPs on AQP1 gene expression was assayed in time- and dose-dependent manners. Results Fur and MGly at the concentrations reported in traditional peritoneal dialysis fluid (Fur 0.8μM; MGly 35μM) significantly up-regulated eNOS mRNA and tended to down-regulate AQP1 mRNA in cultured endothelial cells. Western blot revealed similar results. Conclusion GDPs stimulate eNOS expression in endothelial cells without up-regulating AQP1 expression. These effects may be involved in ultrafiltration failure in long run peritoneal dialysis.

Key words: Aquaporin-1, Endothelial nitric oxide synthase