Inhibition of Hair Growth by Testosterone in the Presence of Dermal Papilla Cells from the Frontal Bald Scalp of the Postpubertal Stumptailed Macaque

The 1996 study involving 3 prepubertal and 16 postpubertal stumptailed macaques found that testosterone inhibited hair growth when interacting with dermal papilla cells from the bald scalps of adult macaques. This effect was not observed with cells from hairy scalps of adult macaques or prebald scalps of juvenile macaques, indicating that the inhibitory effect of testosterone on hair growth is age-dependent. The study also discovered that RU 58841, an androgen receptor blocker, could counteract this inhibition, suggesting its potential use for hair regrowth. Furthermore, the study revealed that bald frontal dermal papilla cells had a slower growth rate and shorter length compared to other cells, and that 5% RU 58841 resulted in significant hair regrowth as early as 2 months after treatment.