Drake L, Hordinsky M, Fiedler V, Swinehart J, Unger W P, Cotterill P C, Thiboutot D M, Lowe N, Jacobson C, Whiting D, Stieglitz S, Kraus S J, Griffin E I, Weiss D, Carrington P, Gencheff C, Cole G W, Pariser D M, Epstein E S, Tanaka W, Dallob A, Vandormael K, Geissler L, Waldstreicher J
University of Oklahoma Health Sciences, Oklahoma City, USA.
J Am Acad Dermatol. 1999 Oct;41(4):550-4.
Data suggest that androgenetic alopecia is a process dependent on dihydrotestosterone (DHT) and type 2 5alpha-reductase. Finasteride is a type 2 5alpha-reductase inhibitor that has been shown to slow further hair loss and improve hair growth in men with androgenetic alopecia.
We attempted to determine the effect of finasteride on scalp skin and serum androgens.
Men with androgenetic alopecia (N = 249) underwent scalp biopsies before and after receiving 0.01, 0.05, 0.2, 1, or 5 mg daily of finasteride or placebo for 42 days.
Scalp skin DHT levels declined significantly by 13.0% with placebo and by 14.9%, 61.6%, 56. 5%, 64.1%, and 69.4% with 0.01, 0.05, 0.2, 1, and 5 mg doses of finasteride, respectively. Serum DHT levels declined significantly (P <.001) by 49.5%, 68.6%, 71.4%, and 72.2% in the 0.05, 0.2, 1, and 5 mg finasteride treatment groups, respectively.
In this study, doses of finasteride as low as 0.2 mg per day maximally decreased both scalp skin and serum DHT levels. These data support the rationale used to conduct clinical trials in men with male pattern hair loss at doses of finasteride between 0.2 and 5 mg.
数据表明雄激素性脱发是一个依赖于二氢睾酮（DHT）和2型5α-还原酶的过程。非那雄胺是一种2型5α-还原酶抑制剂，已被证明可减缓雄激素性脱发男性的进一步脱发并促进头发生长。
我们试图确定非那雄胺对头皮皮肤和血清雄激素的影响。
249名雄激素性脱发男性在接受每日0.01、0.05、0.2、1或5毫克非那雄胺或安慰剂治疗42天前后进行头皮活检。
安慰剂组头皮皮肤DHT水平显著下降13.0%，0.01、0.05、0.2、1和5毫克剂量非那雄胺组分别下降14.9%、61.6%、56.5%、64.1%和69.4%。0.05、0.2、1和5毫克非那雄胺治疗组的血清DHT水平分别显著下降（P<.001）49.5%、68.6%、71.4%和72.2%。
在本研究中，每天低至0.2毫克的非那雄胺剂量可最大程度降低头皮皮肤和血清DHT水平。这些数据支持了在男性雄激素性脱发患者中使用0.2至5毫克剂量非那雄胺进行临床试验的理论依据。
