TLDR Dopamine stops hair growth and pigment production in human scalp hair follicles.
The study from 2012 investigated the effects of dopamine on human scalp hair follicles in vitro, specifically looking at hair growth, pigmentation, and dopamine receptor expression. Treating microdissected human scalp hair follicles from women with dopamine led to a significant induction of catagen phase (hair follicle regression), a decrease in keratinocyte proliferation (P < 0.01), and reduced melanin production within the follicles. Dopamine receptor transcripts were found in both hair follicles and skin. The study, which included groups of 9-39 hair follicles from women aged 47-68, concluded that dopamine acts as an inhibitor of hair growth and could potentially be used to treat unwanted hair growth, while suggesting that dopamine receptor antagonists might promote hair growth. Further research is needed to confirm these findings in a larger sample size and in vivo.
64 citations,
January 2010 in “The FASEB Journal” Prolactin affects the production of different keratins in human hair, which could lead to new treatments for skin and hair disorders.
36 citations,
November 2009 in “Journal of Investigative Dermatology” Prolactin may affect hair growth differently based on gender and scalp area.
132 citations,
September 2009 in “Experimental Dermatology” A reliable system was developed to distinguish hair growth stages, aiding in identifying hair growth promoters or inhibitors.
14 citations,
October 2006 in “Journal of The American Academy of Dermatology” A woman with Parkinson's disease experienced hair loss from the Parkinson's medication pramipexole, which improved after stopping the drug.
37 citations,
May 1999 in “Annals of pharmacotherapy/The annals of pharmacotherapy” Some psychotropic medications can rarely cause hair loss, and stopping these drugs usually reverses the condition.
2 citations,
January 2023 in “International journal of biological sciences” Gray hair can potentially be reversed, leading to new treatments.
130 citations,
August 2015 in “Experimental Dermatology” Human hair follicle organ culture is a useful model for hair research with potential for studying hair biology and testing treatments.
98 citations,
July 2014 in “Trends in Molecular Medicine” Hair follicles are hormone-sensitive and involved in growth and other functions, with potential for new treatments, but more research is needed.
September 2004 in “Experimental dermatology” Melatonin directly affects mouse hair follicles and may influence hair growth.
26 citations,
May 2014 in “BioEssays” Using neurohormones to control keratin can lead to new skin disease treatments.
