Water-only pores and peritoneal dialysis.

The article by Ni et al. solidifies the important role of aquaporin-1 in the process of fluid removal from anephric patients treated with peritoneal dialysis. The presence of the water-only channel in the subperitoneal endothelia provides the mechanism for solute-free ultrafiltrate observed early in dialysis and accounts for approximately half of all the filtration observed in dialysis.