Hernández-Pérez O, Ballesteros L M, Rosado A
Arch Androl. 1979;3(1):23-9. doi: 10.3109/01485017908985044.
The binding of 3H-17-beta-estradiol to human ejaculated spermatozoa and to its subcellular structures was studied. The binding kinetics of the labeled steroid to whole spermatozoa followed a parabolic pattern. Scatchard-type plots showed the presence of high-affinity binding sites (1.56 +/- 0.23 X 10(4) per sperm cell) with an apparent Kd of 6.6 X 10(-10) M. In competition experiments testosterone was partially effective in decreasing 17-beta-estradiol binding, whereas progesterone and 17-alpha-estradiol were ineffective. Study of membrane fractions obtained from estradiol-labeled spermatozoa showed that under saturating conditions 75-84% of the bound steroid was bound to sperm membranes. Nuclear fractions obtained from estradiol-labeled spermatozoa showed only 10% of the total bound radioactivity. When isolated sperm nuclei were incubated in the presence of the purified receptor-17-beta-estradiol complex obtained from the high speed supernatant of human uterus almost no transfer of radioactivity to the nuclei was observed.
研究了³H-17-β-雌二醇与人射出精子及其亚细胞结构的结合。标记类固醇与整个精子的结合动力学呈抛物线型。Scatchard型图显示存在高亲和力结合位点（每个精子细胞1.56±0.23×10⁴个），表观解离常数为6.6×10⁻¹⁰M。在竞争实验中，睾酮在降低17-β-雌二醇结合方面部分有效，而孕酮和17-α-雌二醇无效。对从雌二醇标记精子中获得的膜部分的研究表明，在饱和条件下，75 - 84%的结合类固醇与精子膜结合。从雌二醇标记精子中获得的核部分仅显示总结合放射性的10%。当在从人子宫高速上清液中获得的纯化受体-17-β-雌二醇复合物存在下孵育分离的精子核时，几乎未观察到放射性向核的转移。
