Chronic peritoneal dialysis in iron-deficient rats with solutions containing iron dextran

Background. We evaluated the effects of different concentrations of iron de xtran administered through the intraperitoneal route, in iron-deficient rat s, on hematocrit (Hct in percentage), serum iron (mg/dL). total iron bindin g capacity (TIBC in mg/dL), and the function and histology of the peritonea l membrane. Methods. Seventy-two male Sprague-Dawley rats weighing 85 to 110 g were div ided into two groups and seven subgroups. Group I consisted of rats on iron -deficient chow, and group II consisted of rats on normal chow. Both groups contained dialysis control subgroups (N = 12: IA. IID). dialyzed with Dian eal(R) solution, and tissue control subgroups (N = 6: IE, IIN), in which ra ts were not dialyzed and catheters were nor implanted. Study group I contai ned the following study subgroups (N = 12): (B) rats dialyzed with Dianeal( R) solution containing 2 mg/L of iron dextran and (C) rats dialyzed with Di aneal(R) solution containing 1 mg/L of iron dextran. Group IID was dialyzed with Dianeal(R) solution containing 2 mg/dL of iron dextran. Study duratio n was 12 weeks with peritoneal equilibration tests (PETs) performed at base line. 6 weeks, and 12 weeks. Prior to baseline, rats were placed on Iron-de ficient chow or normal chow for three weeks. Dialysis was performed with th ree 25 mt volume exchanges per day. Hematocrit (Hct), serum iron (Fe), and total iron binding capacity (TIBC) were determined for each study interval. After the final PET, the animals were sacrificed, and the peritoneal membr ane was evaluated by gross inspection and light microscopy. Results. Rats on an iron-deficient diet developed severe iron-deficiency an emia after three weeks of the diet (Hct 27: Fe 21 to 23: TIBC 799 to 806). After 12 weeks, the rats remained anemic in groups A (Hct 34 +/- 0.9; Fe 16 +/- 2; TIBC 998 +/- 27) and IE (Hct 38 +/- 2.7), whereas the rats correcte d anemia in group B (Hct 45.8 +/- 1.8; Fe 115 +/- 15: TIBC 546 +/- 77). The results were not significantly different from those of group IID (Hct 47.1 +/- 1.6: Fe 94 +/- 19, TIBC 516 +/- 46). In group C Her (44.8 +/- 2.1) and Fe (94 +/- 19) did not differ significantly from group IID: but TIBC (734 +/- 76) remained significantly higher than that In the group IID. Peritonea l iron deposits were not detected. The morphometric analysis of the submeso thelial space did not reveal any difference in thickness between dialysis g roups. PETs were not significantly different among groups. Conclusions. Intraperitoneal iron dextran supplementation in concentrations of 2 mg/L of dialysis solution is nontoxic to the peritoneum and effective in correcting iron deficiency in rats maintained on an iron-deficient diet . Iron dextran in concentration of 1 mg/L of dialysis solution may be suffi cient for correcting a lesser degree of iron deficiency.