Renal enzymes in kidney cells selected by D‐valine medium

The ability of D‐valine medium to inhibit fibroblasts in cultures derived from kidneys of various mammals has enabled the selective proliferation of epithelial cells in the absence of fibroblast overgrowth. Studies of these selected epithelial cells have demonstrated the presence of D‐amino acid oxidase, carbonic anhydrase, high levels of alkaline phosphatase and the renal specific pattern of lactate dehydrogenase. The presence of these renal enzymes suggests that the selected epithelial cells are of renal tubular origin and indicates that these differentiated functions are retained in cultured cells.