Hair Follicle Biology and Topical Minoxidil: Possible Mechanisms of Action
January 1987
in “
Dermatology
”
topical minoxidil androgenetic alopecia mesenchymal cells follicular dermal papilla stromal-epithelial interaction hair matrix cells hair matrix volume hair shaft diameter anagen phase hair cycle PGI formation keratinocytes lysyl hydroxylase fibroblasts K channel agonist vascular smooth muscle Rogaine hair growth hair follicle hair thickness hair growth phase skin cells collagen synthesis potassium channel opener
TLDR Minoxidil stimulates hair growth by increasing hair thickness and prolonging growth phase.
This article discusses the possible mechanisms of action of topical minoxidil in stimulating hair growth in androgenetic alopecia. Topical minoxidil may act on the specialized mesenchymal cells of the follicular dermal papilla to maintain or enhance normal dynamics of the essential stromal-epithelial interaction between the dermal papilla and the proliferating hair matrix cells. The hypertrophic effect of minoxidil includes an increase in hair matrix volume, which may lead to an increase in hair shaft diameter and a thicker hair. There is good circumstantial proof that topical minoxidil prolongs the anagen phase of the hair cycle, which may result in longer hair growth. The precise mechanisms for the trichotrophic action of minoxidil remain unknown, but it has been observed to inhibit PGI formation in cultured human keratinocytes, inhibit the synthesis of lysyl hydroxylase in cultured human fibroblasts, and act as a K channel agonist in human vascular smooth muscle.
