Departments of Molecular, Cellular and Developmental Biology and Veterinary Anatomy, Pharmacology and Physiology, Iowa State University, Ames, Iowa 50011 U.S.A.
Abstract:
The effects of lead upon collagen synthesis and proline hydroxylation were examined in the Swiss mouse 3T6 fibroblast. The results indicate that lead reduces proline hydroxylation in stationary phase cultures of 3T6 cells, resulting in increased cellular retention of unhydroxylated procollagen. Inhibition of proline hydroxylation by lead was prevented by increasing the extracellular molar ratio. Interference by lead in the hydroxylation of proline in logarithmic phase cultures of 3T6 cells resulted in increases in the 0.5 n HClO4 soluble/insoluble hydroxyproline ratio. This was attributed to an increase in the rate of breakdown of lead-induced unhydroxylated procollagen. Kinetic analysis of the lead-iron interaction with proline hydroxylase suggests that the mechanism is competitive.