Wu J T, Williams K I
Department of Obstetrics and Gynecology, University of Massachusetts Medical Center, Worcester 01655.
Steroids. 1989 Oct;54(4):401-19. doi: 10.1016/0039-128x(89)90053-6.
When day 6 rabbit blastocysts were cultured (3 embryos/mL) in medium 199 containing 3.68 microM estradiol-17 beta (E2), 40% of E2 was metabolized in 24 h, at a rate of 18 pmol/embryo(b)/h, yielding 4 major metabolite fractions. Two of them were identified to be estrogen glucosides: 17 beta-hydroxyestra-1,3,5(10)-trien-3-yl beta-D-glucopyranoside (E(2)3G) (12 pmol/b/h) and 17-oxoestra-1,3,5(10)-trien-3-yl beta-D-glucopyranoside (E(1)3G) (0.5 pmol/b/h). If the blastocysts were cultured in 3.68 microM E1 medium, 75% of E1 was metabolized in 24 h (34.1 pmol/b/h); most of it appears as E2 (8 pmol/b/h), E(1)3G (16 pmol/b/h), and E(2)3G (6 pmol/b/h). Thus, the 17 beta-hydroxysteroid dehydrogenase activity in the rabbit blastocysts catalyzes mainly in the direction of the E1----E2 conversion, with little or no E2----E1. This may be responsible in part for the faster metabolism of E1 than E2 by the rabbit blastocyst. In comparison with the rat, mouse, and hamster blastocyst, the rabbit embryo shows an additional capability to conjugate large amounts of estrogens into glucosides by steroid glucosyltransferase.
将第6天的兔胚泡（3个胚胎/毫升）在含有3.68微摩尔17β-雌二醇（E2）的199培养基中培养时，40%的E2在24小时内被代谢，代谢速率为18皮摩尔/胚胎（b）/小时，产生4个主要代谢物组分。其中两个被鉴定为雌激素葡糖苷：17β-羟基雌-1,3,5（10）-三烯-3-基β-D-吡喃葡萄糖苷（E（2）3G）（12皮摩尔/ b /小时）和17-氧代雌-1,3,5（10）-三烯-3-基β-D-吡喃葡萄糖苷（E（1）3G）（0.5皮摩尔/ b /小时）。如果将胚泡在3.68微摩尔E1培养基中培养，75%的E1在24小时内被代谢（34.1皮摩尔/ b /小时）；大部分代谢产物表现为E2（8皮摩尔/ b /小时）、E（1）3G（16皮摩尔/ b /小时）和E（2）3G（6皮摩尔/ b /小时）。因此，兔胚泡中的17β-羟基类固醇脱氢酶活性主要催化E1向E2的转化方向，很少或几乎没有E2向E1的转化。这可能部分解释了兔胚泡对E1的代谢比E2更快的原因。与大鼠、小鼠和仓鼠胚泡相比，兔胚胎表现出通过类固醇葡糖基转移酶将大量雌激素结合成葡糖苷的额外能力。
