AN IN-VITRO MODEL OF RENAL PROXIMAL TUBULE CELL REGENERATION

The ability of renal cells to regenerate is critical for the recovery of renal function following injury. Research on the recovery of renal function has been limited by the lack of in vitro models of renal repa ir. The goal of this study was to develop an in vitro model of renal p roximal tubule cell (RPTC) injury and regeneration using primary cultu res of rabbit RPTC. Renal proximal tubules were isolated and cultured in hormonally defined DME/F-12 medium at 37-degrees-C under 95% air/5% CO2. RPTC were grown to confluency, made quiescent by the removal of insulin and hydrocortisone from the medium for 24-48 hr, and treated w ith the nephrotoxicant, 1,2-dichlorovinyl-L-cysteine (DCVC). DCVC (100 muM for 2 hr, n = 3-6) resulted in cell injury and the release of non viable cells from the plate at 24 hr (55% +/- 6% confluency. mean +/- SEM) and 48 hr (37% +/- 7% confluency). Cell monolayers began to regen erate 96 hr after exposure (57% +/- 9% confluency) and continued to re generate reaching 76% +/- 8% and 84% +/- 1% confluency by 6 and 8 days postexposure. Control cells maintained confluency throughout the expe riment. Thus, an in vitro primary cell culture model has been develope d in which the cell monolayer regenerates after nephrotoxicant-induced injury. This model may be useful in the study of mechanisms of renal cell injury and repair.