The Effect of Minoxidil on Cultured Mouse Fibroblast

ABSTRACT

Proliferative vitreoretinopathy is characterized by proliferation of retinal pigment epithelial cells, fibroblasts, glial cells and excessive fibrous tissue production. Recently minoxidil has been found to inhibit the proliferation of cultured fibroblast and retinal pigment epithelium. Minoxidil also inhibits the mRNA expression and protein production of lysyl hydroxylase, a key-enzyme involved in cross-linking of collagen. Therefore, the author investigated the effects of minoxidil on cultured mouse fibroblast and the result was compared with those of 5-fluorouracil and dexamethasone. Dexamethasone demonstrated bimodal effect of stimulation of proliferation at low concentrations and inhibition at higher concentrations. Fifty percent inhibition of growth (ID50) was seen at a concentration of 316mg/L. 5-fluorouracil had the most potent antiproliferative activity with ID50 of 0.8mg/L. Minoxidil had more potent antiproliferative properties on cultured mouse fibroblasts than dexamethasone. Fifty percent inhibition of growth (ID50) was 200mg/L. Reduction in cell number was seen after a 30 minute treatment and was half-maximal after 48 hours of treatment with 1000mg/L minoxidil.