Peritoneal capillary–interstitium–peritoneal cavity interface

The peritoneal capillary–interstitium–peritoneal cavity interface is a complex physiological barrier that regulates the exchange of water and solutes between the blood and the peritoneal space (Krediet, 1999). This interface consists of three distinct layers: the capillary endothelium, the interstitial tissue, and the mesothelial cell layer (Krediet, 1999). In the context of peritoneal dialysis, this system functions as a semi-permeable membrane where transport is governed by the Three-Pore Model, involving large pores, small pores, and ultra-small transcellular pores, specifically Aquaporin-1 (Rippe & Levin, 2000; Devuyst et al., 2002). The interface is the primary site of action for dialysis solutions containing osmotic agents like glucose or icodextrin, which create the necessary gradients for ultrafiltration and waste removal (Gokal & Mallick, 1999). Pathological changes such as mesothelial-to-mesenchymal transition, angiogenesis, and fibrosis—often driven by chronic exposure to high glucose concentrations or inflammation—can lead to membrane failure and encapsulating peritoneal sclerosis (Davies et al., 2001). Understanding the electrochemical and osmotic dynamics of this interface is critical for optimizing dialysis efficacy and preserving long-term membrane function in patients with end-stage renal disease.

Other names

Peritoneal membranePeritoneal barrierPeritoneal transport interface

Facilitation of diffusive and convective transport across a semi-permeable biological barrier via osmotic and electrochemical gradients.