Hoffmann R, Happle R
Department of Dermatology, Philipp University, Deutschhausstr. 9, D-35033 Marburg, Germany.
Eur J Dermatol. 2000 Jun;10(4):319-27.
Androgenetic alopecia (AGA) is the most common type of hair loss in men and women. This continuous process results in a type of alopecia that follows a definite pattern in those individuals who are genetically predisposed. At present the predisposing genes are unknown but the relatively strong concordance of the degree of baldness in fathers and sons is not consistent with a simple Mendelian trait and a polygenic basis is therefore most likely. AGA can be defined as a DHT-dependent process with continuous miniaturization of sensitive HF. Today we do not understand the molecular steps involved in androgen-dependent beard growth versus androgen-dependent hair loss in AGA. However, recent experimental and clinical advances enable us to explain some pathogenetic steps leading to androgenetic hair loss. Among other steroidogenic isoenzymes such as 17b- and 3b- hydroxysteroid dehydrogenases, the type 2 5a-reductase within the dermal papilla plays a central role by the intrafollicular conversion of T to DHT.
雄激素性脱发（AGA）是男性和女性中最常见的脱发类型。这种持续的过程会导致一种脱发，在那些有遗传易感性的个体中呈现出明确的模式。目前，易感基因尚不清楚，但父子间脱发程度相对较强的一致性并不符合简单的孟德尔性状，因此最有可能是多基因基础。AGA可定义为一个依赖双氢睾酮（DHT）的过程，在此过程中敏感毛囊持续小型化。如今，我们并不了解雄激素依赖的胡须生长与AGA中雄激素依赖的脱发所涉及的分子步骤。然而，最近的实验和临床进展使我们能够解释一些导致雄激素性脱发的发病机制步骤。在其他类固醇生成同工酶如17β-和3β-羟基类固醇脱氢酶中，真皮乳头内的2型5α-还原酶通过毛囊内睾酮向双氢睾酮的转化发挥核心作用。
