Yeko T R, Khan-Dawood F S, Dawood M Y
Department of Obstetrics and Gynecology, University of Illinois College of Medicine, Chicago 60612.
J Clin Endocrinol Metab. 1989 Mar;68(3):529-34. doi: 10.1210/jcem-68-3-529.
To characterize and determine the concentration of LH/hCG receptors in human corpora lutea of the menstrual cycle, we measured occupied and unoccupied receptors and determined the association (Ka) and dissociation (Kd) constants individually in 23 corpora lutea (CL) and 4 corpora albicantia obtained at the time of tubal ligation from 25 normal cycling women. We found no [125I]hCG binding in any of the corpora albicantia. Scatchard plot analysis for each CL revealed a linear binding plot indicative of a single set of LH/hCG receptors. The mean concentration of unoccupied receptors was 36 +/- 10 (+/- SE) fmol/mg protein in the early luteal phase (days 15-19; n = 5), 64 +/- 11 fmol/mg protein in the midluteal phase (days 20-25; n = 13), and 42 +/- 19 fmol/mg protein in the late luteal phase (days 26-30; n = 5). The concentrations of occupied receptors were 56 +/- 8, 46 +/- 6, and 54 +/- 12 fmol/mg protein in the early, mid-, and late luteal phases, respectively. Total (occupied plus unoccupied) receptor concentrations reached maximum levels of 110 +/- 11 fmol/mg protein in the midluteal phase. Ka increased progressively from 12 +/- 4 X 10(9) mol/L-1 in the early luteal phase to 19 +/- 7 X 10(9) and 21 +/- 8 X 10(9) mol/L-1 in the mid- and late luteal phases. We conclude that in normal CL, 1) total and unoccupied LH/hCG receptor levels parallel progesterone secretion; 2) changes in the binding affinity may be important in sustaining and/or rescuing the CL; and 3) loss of LH/hCG receptors is probably related to luteolysis.
为了表征并确定月经周期中人类黄体生成素/人绒毛膜促性腺激素（LH/hCG）受体的浓度，我们对25名正常月经周期女性在输卵管结扎时获取的23个黄体（CL）和4个白体进行了测量，分别测定了被占据和未被占据的受体，并确定了其结合常数（Ka）和解离常数（Kd）。我们在任何白体中均未发现[125I]hCG结合。对每个黄体的Scatchard图分析显示为线性结合图，表明存在单一的LH/hCG受体组。未被占据受体的平均浓度在黄体早期（第15 - 19天；n = 5）为36 ± 10（± SE）fmol/mg蛋白，黄体中期（第20 - 25天；n = 13）为64 ± 11 fmol/mg蛋白，黄体晚期（第26 - 30天；n = 5）为42 ± 19 fmol/mg蛋白。被占据受体的浓度在黄体早期、中期和晚期分别为56 ± 8、46 ± 6和54 ± 12 fmol/mg蛋白。总（被占据加未被占据）受体浓度在黄体中期达到最高水平，为110 ± 11 fmol/mg蛋白。Ka从黄体早期的12 ± 4×10⁹ mol/L⁻¹逐渐增加到黄体中期和晚期的19 ± 7×10⁹和21 ± 8×10⁹ mol/L⁻¹。我们得出结论，在正常黄体中，1）总LH/hCG受体水平和未被占据的LH/hCG受体水平与孕酮分泌平行；2）结合亲和力的变化可能对维持和/或挽救黄体很重要；3）LH/hCG受体的丧失可能与黄体溶解有关。
