Very high daily intraperitoneal doses of carbonyl compounds affect the morphology, but not the exchange characteristics, of rat peritoneum

Glucose degradation products (GDP) are carbonyl compounds, that are formed by heat sterilization of conventional peritoneal dialysis (PD) fluids. Carb onyl compounds are known to be toxic in vitro and potentially toxic also in vivo. The aim of this study was to evaluate the effects of daily, short-te rm exposure of the peritoneum to very high concentrations of GDP in vivo on peritoneal transport parameters and on peritoneal morphology in a well-est ablished rat model of PD. Rats were exposed to three daily intraperitoneal (IP) injections (10 ml) for 9 days of a largely neutral (pH 7.2) PD fluid c ontaining 1.5% glucose and sterilized by filtration, with (n = 8) or withou t (n = 8) the presence of different carbonyl compounds in concentrations 10 0 times higher than those reported in commercial PD fluids. Seven rats, not subjected to any exposure, served as controls. After the exposure, the rat s were subjected to acute PD in 4-hour dwells. Twenty milliliters of 4% glu cose dialysis fluid were instilled into the rat peritoneal cavity. Blood an d dialysate samples were taken during the dwell for measurements of dialysa te sodium, and for assessments of the mass transfer area coefficient (PS) f or glucose and Cr-51-EDTA and of transperitoneal clearance (CI) or radiolab elled albumin (RISA). At the end of the dwell, parts of the liver, diaphrag m and peritoneum were removed for measurements of tissue cell density and t hickness of the submesothelial peritoneal tissue. The exposure of the perit oneum to very high doses of carbonyl compounds did not affect the peritonea l transport of fluid and small solutes significantly, but seemed to slightl y reduce lymph flow and albumin clearance out of the peritoneal cavity. Ass essed after a hypertonic dwell, and compared to the situation in nontreated rats after the same kind of dwell, there was a significant thinning of the submesothelial tissue, but no difference in tissue cell density. It is con cluded that short-term exposure of the peritoneum in vivo to very high dose s of GDP resulted in almost no signs of acute toxicity. Copyright (C) 2001 S. Karger AG, Basel.