Uptake kinetics and the effect of minoxidil on human keratinocyte cultures.
The antihypertensive drug minoxidil (Lonolox) is rapidly taken up by human keratinocytes (HaCaT-cells). After 3 h the uptake is half of its maximum. Specific minoxidil receptors could not be found. High minoxidil concentrations (greater than 100 micrograms/ml) inhibited the incorporation of thymidine into DNA (ED50 = 263 micrograms/ml) and the incorporation of amino acids into proteins (ED50 = 251 micrograms/ml). The inhibition was reversible up to a concentration of 400 micrograms/ml. In the presence of 100 micrograms/ml minoxidil, the cell division remained active for a longer period of time and a higher cell density was achieved as opposed to the parallel control group. A prolongation of the proliferative capability of keratinocytes may be partially responsible for the positive effect of minoxidil on hair growth.
Bernd
A
A
Zentrum der Dermatologie und Venerologie, Johann Wolfgang Goethe-Universität, Frankfurt/Main, Fed. Rep. of Germany.
Breuer
M
M
Dold
K
K
Holzmann
H
H
D000596:Amino Acids / Q000378:metabolism; D002478:Cells, Cultured; D006367:HeLa Cells; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism*; D008914:Minoxidil / Q000493:pharmacokinetics* / Q000494:pharmacology; D013936:Thymidine / Q000378:metabolism
D000596:Amino Acids; D008914:Minoxidil; D013936:Thymidine