Deplewski D, Liao S, Rosenfield R L
The University of Chicago, Pritzker School of Medicine, Department of Pediatrics, Illinois 60637-1470, USA.
Endocrinology. 1997 Oct;138(10):4416-20. doi: 10.1210/endo.138.10.5452.
We determined whether the 5alpha-reductase (5alpha-R) isozyme specificity in rat preputial sebocytes is in accordance with that of sebaceous glands (type 1 isoform) or with that of other genital tract androgen-dependent organs (type 2). Immunostaining indicated expression of type 1 5alpha-R in preputial epithelial cells in the gland as well as in culture. Northern blots and ribonuclease protection assays both showed the presence of the type 1 isozyme in preputial sebocytes, with little if any expression of the type 2 messenger RNA. Ribonuclease protection assay demonstrated that both homogenized preputial gland and freshly dispersed preputial cells express 2-fold more 5alpha-R type 1 messenger RNA than does skin and 7-fold more than cultured preputial cells. Since cultured preputial cells do not fully differentiate in monolayer culture, these findings suggest that 5alpha-R is increasingly expressed as sebaceous cells differentiate. The predominance of the type 1 isoform in preputial sebocytes is important because it indicates programming by a skin- and sebocyte-specific signal in the midst of the genital tract where the type 2 isoform otherwise predominates.
我们确定了大鼠包皮皮脂腺细胞中5α-还原酶（5α-R）同工酶的特异性是否与皮脂腺（1型同工型）或其他生殖道雄激素依赖器官（2型）的特异性一致。免疫染色表明，1型5α-R在腺体以及培养物中的包皮上皮细胞中均有表达。Northern印迹和核糖核酸酶保护试验均显示包皮皮脂腺细胞中存在1型同工酶，2型信使核糖核酸几乎没有表达。核糖核酸酶保护试验表明，匀浆的包皮腺和新鲜分散的包皮细胞表达的1型5α-R信使核糖核酸比皮肤多2倍，比培养的包皮细胞多7倍。由于培养的包皮细胞在单层培养中不能完全分化，这些发现表明5α-R随着皮脂腺细胞的分化而表达增加。包皮皮脂腺细胞中1型同工型的优势很重要，因为它表明在生殖道中，2型同工型占主导地位的情况下，存在一种由皮肤和皮脂腺细胞特异性信号进行的编程。
