In vitro study of the effect of osmotic solutes on the interactions between cells from the peritoneum and peritoneal cavity.

Objective: To study how the presence of osmotic solutes in medium affects growth of the peritoneal mesothelial cells and fibroblasts and how osmotic solutes influence the production of factors regulating growth of these cells.

Design: The proliferation of mesothelial cells and fibroblasts was evaluated by measuring the incorporation of 3H-thymidine into the cells. Cells were exposed to osmotic solutes; the concentration of the latter in the medium was continuously lowered over the time of the experiment to simulate changes of their concentration in the dialysate.

Effect of phosphatidylcholine on the function of human mesothelial cells in vitro.

We tested the hypothesis that phosphatidylcholine (PC) molecules present in the dialysis solution may interact with the mesothelial cell membrane and modify its function. In vitro experiments were performed on human mesothelial cells (HMC) in culture. PC decreased proliferation of HMC when used at concentrations of 200 mg/l and higher.

Toxicity of free radicals to mesothelial cells and peritoneal membrane.

We studied the toxicity of free radicals to human mesothelial cells in vitro and to the peritoneal membrane of rats during peritoneal dialysis. Free radicals cause damage to mesothelial cells as measured by release of cytosolic markers such as 86Rb and lactate dehydrogenase. Vitamin E neutralized the toxic effect of free radicals in vitro.

In vitro study of the mechanism of potassium transport into human mesothelial cells. I: Effect of hyperosmolality.

Objective: To study the mechanism(s) of potassium transport into human mesothelial cells (HMC) exposed to osmotic solutes.

Design: Using potassium analog 86Rb, we evaluated its intracellular transport through three pathways: 1. blocked by ouabain; 2.

Amino acid solutions for CAPD: rationale and clinical experience.

Protein-calorie malnutrition is present in a sizable proportion of dialysis patients. In CAPD patients, constant glucose absorption from dialysate may displace other calorie sources, such as protein, and may suppress the appetite, thus contributing to malnutrition. Use of amino acids in place of glucose as the osmotic agent has been studied extensively.