Expression Of Aquaporin 1 In The Peritoneum Of ESRD Patient

ObjectiveAquaporins are a group of water-selective channel proteins.They are very important in maintaining fluid balance of organism.Until now,fourteen isoforms have been found.AQP1 was the first member being found in this family.AQP1 have been claimed to be responsible for osmotically driven water movement across the peritoneal membrane.Present study was performed to observe the expression of AQP1 in peritoneum,and investigate the relationship between AQP1 and Ccr,UF and Urine volume.The clinical significance of AQP1 in selection and outcome of peritoneal dialysis was confirmed further.Methods1.Peritoneal biopsies were obtained from normal subjects,uremic patients at catheter insertion and PD patients at the time of catheter removal or reinsertion.2.Expression of AQP1 in peritoneum was detected by means of immunohistochemistry and a semiquantitative scoring system.3.Expression of AQP1mRNA in peritoneum was detected by means of PCR.4.Clinical data of all patients were collected.Data about uremic patients after PD including UF,urine volume and etc.5.Analyze the relationship between AQP1 and patient's Ccr,UF and Urine volume.Results1.The positive deposits were very specific,with distribution in the mesothelial cells,endothelial cells of capillaries,venules and small veins,whereas no signal was detected in the arterioles.2.By means of immunohistochemistry and PCR,there was no statistical significance between the normal subjects and uremic patients.3.Compare the AQP1 average score between the group of Ccr＞10 ml/min with the group of Ccr≤10 ml/min.There is no statistical significance between these two groups.4.The quantitity of serum albumin may have no effect with the expression of AQP1,ultrafiltration per bag or per day.5.There was no obviously direct correlation between serum CRP and the expression of AQP1.6.There is no obvious correlation between AQP1 and ultrafiltration per bag or per day.Conclusion1.Long term peritoneal dialysis may not affect the expression level of AQP1. Structural and functional alterations of AQP1,rather than its expression level, might play a role in ultrafiltration failure.2.AQP1 should not be a good marker in evaluating peritoneal transportation.3.The quantitity of serum albumin may have no effect with the expression of AQP1 and ultrafiltration.Further study is needed to determine the structural and functional alterations.