Objective To observe the effect of icodextrin on peritoneal membrane angiogenesis in continuous ambulatory peritoneal dialysis (CAPD) patients. Methods This was a randomized double-blind perspective study of CAPD patients at our center between January 2006 to December 2006. The patients were randomized to receive either 7. 5% icodextrin ( ICO, n = 27) or glucose (GLU, n = 27) solution at night for 4 weeks. Peritoneal membrane function was defined as dialysate dwell for 4 hours to plasma ratio of creatinine (4 h D/Pcr) at baseline. Ultrafiltration volume, creatinine clearance (Ccr), VEGF and IL-6 in peritoneal effluent during the long night dwell (UF) dialysate were measured at baseline and after 4 weeks.The VEGF appearance was used to adjust the influences of dwell time and ultrafiltration volume. Results A total of 54 patients were enrolled. The baseline conditions showed no difference between the groups. After 2 and 4 weeks of therapy, both net UF and peritoneal creatinine clearance of long dwell were significantly higher in the ICO group than the GLU group. VEGF in night dwell PD solution was positively correlated with D/PCr(r = 0. 68, P < 0. 01 ) and negatively correlated to 4 hour ultrafiltration volume ( r = - 0. 51, P< 0. 01 ). The VEGF appearance was comparable between two groups at baseline. After a follow-up of 4 weeks, the VEGF appearance had an increasing tendency in the GLU group and a decreasing tendency in the ICO group but there was no significant difference. The △VEGF appearance ( VEGF appearance in 4 weekVEGF appearance at baseline) was different between the GLU and ICO groups (9. 5 ±20. 2 vs - 13. 4 ±26. 1,P< 0.01). IL-6 in night dwell dialysate had no difference between two groups. Conclusion As compared with glucose-based solution, 7. 5% icodextrin significantly decreases the local VEGF level in dialysate.[ Key words] U ltrafiltration; Vascular endothelial growth factors; Neovascularization, pathologic