title: Effect of bicarbonate/lactate peritoneal dialysis solutions on human mesothelial cell proliferation ex vivo.
abstract: Peritoneal membrane suffers structural and functional changes over time on peritoneal dialysis (PD)--in part, owing to the dialysis solutions currently used. Low pH seems to be an important element associated with solution bioincompatibility. Bicarbonate-containing fluids open new perspectives on this issue. The present study compared the effects of bicarbonate/lactate (Bic/Lac) solution (25 mmol/L bicarbonate, 15 mmol/L lactate) and lactate (Lac) solution (40 mmol/L lactate) on mesothelial cell (MC) growth in culture. Eight stable PD patients were asked to collect peritoneal effluent from an 8-hour dwell on two separate days, within an interval shorter than one week. For the first dwell, Lac solution was infused; for the second dwell, Bic/Lac solution was instilled. Human MCs were isolated from the effluent, seeded in 25-cm2 tissue culture flasks, and grown ex vivo. Morphology of the cells was also evaluated. In all effluents, MCs were present in mean amounts of 26,939 +/- 21,267 cells (Bic/Lac) and 25,986 +/- 15,286 cells [Lac, p = nonsignificant (NS)]. Morphology of the MCs was similar with both solutions (87.5% typical). After initial culture, MCs from 6 patients using Bic/Lac (75%) and 3 patients using Lac (37.5%) reached confluence. At this time, the number of MCs from the 3 patients who showed MC growth with both solutions was slightly higher with Bic/Lac-buffered fluid (Lac: 1,154,125 +/- 213,333 cells; Bic/Lac: 1,198,291 +/- 806,713 cells). To summarize: 3 patients showed MC growth under both solutions; 3 patients showed MC growth only under Bic/Lac solution; and 2 patients showed no MC growth at all. After cells were seeded in 24-well plates, the MC growth curve was performed in 4 cases of Bic/Lac solution use and in 3 cases of Lac solution use. Although no significant differences were observed between the solutions, the final number of MCs obtained was higher with Bic/Lac solution use. In conclusion, MCs released into peritoneal effluent under bicarbonate/lactate-buffered peritoneal dialysis solution are associated with a greater ex vivo proliferation capacity than those released under lactate solution in the same patient. This finding may demonstrate better biocompatibility for Bic/Lac solution.
authors.affiliation: Hospitales Universitarios La Paz, Madrid, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Bajo
authors.forename: G
authors.initials: G
authors.lastname: del Peso
authors.forename: M A
authors.initials: MA
authors.lastname: Castro
authors.forename: C
authors.initials: C
authors.lastname: Díaz
authors.forename: M J
authors.initials: MJ
authors.lastname: Castro
authors.forename: F
authors.initials: F
authors.lastname: Gil
authors.forename: J A
authors.initials: JA
authors.lastname: Sánchez-Tomero
authors.forename: R
authors.initials: R
authors.lastname: Selgas
mesh_terms: D001639:Bicarbonates / Q000494:pharmacology*; D001672:Biocompatible Materials; D002452:Cell Count; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D015314:Dialysis Solutions / Q000494:pharmacology*; D004847:Epithelial Cells / Q000166:cytology* / Q000187:drug effects / Q000648:ultrastructure; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019344:Lactic Acid / Q000494:pharmacology*; D008875:Middle Aged; D010530:Peritoneal Dialysis; D010537:Peritoneum / Q000166:cytology* / Q000187:drug effects / Q000648:ultrastructure
chemical_list: D001639:Bicarbonates; D001672:Biocompatible Materials; D015314:Dialysis Solutions; D019344:Lactic Acid