Porphyrin synthesis by murine epidermal cells.

Incubation of murine epidermal cells with delta-aminolevulinic acid (ALA) resulted in a dose- and time-dependent accumulation of porphyrins, predominantly of protoporphyrin. Porphyrin accumulation decreased in the presence of iron, and the iron-mediated decrease was partially reversed by CaMg EDTA (1.25-10.0 mM), suggesting that there is functionally active ferrochelatase in these cells. This study suggests that these cells may be a useful model for the study of cutaneous porphyrin metabolism involving ferrochelatase activity.