Transmesothelial Ultrafiltration IN VITRO

Abstract

The authors created transmesothelial ultrafiltration in vitro by inducing an osmotic gradient (vasc-300 mOsm: meso-400 mOsm) across the membrane. Calculated value of hydraulic conductivity of the mesothelium is comparable with analogous value for endothelium of the microvessels.

They propose that transperitoneal ultrafiltration develops in two phases: Transmesothelial ultrafiltration, which augments tonicity of the interstitial tissue which is followed by transendothelial ultrafiltration due to the osmotic gradient between the dehydrated interstitium and the vascular space. Hypertonic medium on the mesothelial side of the membrane modified its permeability to various solutes: transport rate of urea and inulin was increased whereas transport rate of albumin decreased.

Transperitoneal ultrafiltration of fluid during peritoneal dialysis conditions the removal of water from the organism. According to Nolph et al, the endothelium of the peritoneal microvessels plays a crucial role in this process (I). Little is known about the role of the mesothelium in transperitoneal ultrafiltration but patients with damaged mesothelium show decreased removal of water across the peritoneal membrane (2).

This paper describes the results of an in vitro study on the transmesothelial, osmotically induced ultrafiltration.