L l6 - hsd2 is localized to the sppytiotrophoblast of the placenty providing a fimctional barrier protecting the fetus from matemal glucocorticoids . a sequence resembling glucocorticoid response element ( gre ) has been identified in the promoter region of the human l l0 - hsdl gene . glucocorticoids have been shown to induce the expression of 11p - hsdl in the hippomus in vitro " whereas controversial results were obtained in the hepatocyte 体内至少存在两型11 - hsd ,在细胞完整的状态下, 11 - hsd1主要为还原酶,它活化gc的代谢产物17 -羟- 11 -脱氢皮质酮(啮齿类为脱氢皮质酮)为有活性的皮质醇(啮齿类为皮质酮) ,而11 - hsd2为氧化酶,它催化皮质醇为无活性的17 -羟- 11 -脱氢皮质酮,因此11 - hsd1加强gc的作用,而11 - hsd2减弱gc的作用。