Tandon A, Singh M M, Kamboj V P
Exp Clin Endocrinol. 1983 Nov;82(3):285-90. doi: 10.1055/s-0029-1210288.
Twenty four hour incubations of the days 5 and 6 pre-implantation and the days 7 and 8 post-implantation rabbit embryos were carried out in the presence of 3H-labelled steroid substrates viz. dehydroepiandrosterone (DHEA), androstenedione (Ad) and testosterone (Te). While both the pre- as well as the post-implantation embryos were able to actively metabolize the various neutral steroid substrates into other neutral, mostly 5 alpha-reduced, steroid metabolites, the conversion of DHEA to Ad or that of DHEA, Ad and Te to estrogens was exhibited only by the days 7 and 8 post-implantation embryos. The findings suggest that pre-implantation blastocysts of rabbit lack the potentiality to synthesize steroids and acquire this ability only after implantation.
对植入前第5天和第6天以及植入后第7天和第8天的兔胚胎进行24小时培养，培养在含有3H标记的类固醇底物即脱氢表雄酮（DHEA）、雄烯二酮（Ad）和睾酮（Te）的条件下进行。虽然植入前和植入后的胚胎都能够将各种中性类固醇底物积极代谢为其他中性的、大多是5α-还原的类固醇代谢物，但只有植入后第7天和第8天的胚胎表现出将DHEA转化为Ad，或将DHEA、Ad和Te转化为雌激素的能力。这些发现表明，兔植入前的囊胚缺乏合成类固醇的潜力，只有在植入后才获得这种能力。
