Pediatric Research Center, New Children's Hospital, University of Helsinki and Helsinki University Hospital, Biomedicum II, 6th floor, Tukholmankatu 8 A, FIN-00290, Helsinki, Finland.
HUSLAB, Helsinki University Hospital, Helsinki, Finland.
Hormones (Athens). 2022 Sep;21(3):413-420. doi: 10.1007/s42000-022-00368-9. Epub 2022 May 26.
In our earlier study, we separated three different molecular forms of urinary LH-ir (U-LH-ir) by gel filtration and identified them by immunoassay in urine from regularly menstruating women on periovulatory days. U-LH-ir is composed of intact luteinizing hormone (LH), its free beta-subunit (LHβ), and the core fragment of LHβ (LHβcf), the latter two establishing the non-intact portion of LH-ir. The aim was to determine whether timing of ovulation can be improved by detecting different molecular forms of U-LH-ir in women of reproductive age.
We determined intact and total U-LH-ir in 14 regularly menstruating women on consecutive periovulatory days during the menstrual cycle. Non-intact LH-ir was calculated as the arithmetic difference between total and intact LH-ir. In addition, LH-ir was determined in both serum and urine from four of the women throughout the menstrual cycle.
During the LH surge, U-LH-ir consisted mainly of intact LH and presented with an abrupt increase. Intact U-LH-ir dropped rapidly within 1 day after the surge, reaching baseline levels at the end of the luteal phase. In contrast, LHβcf in urine increased further 1 day after the surge. After this, most of the U-LH-ir consisted of LHβcf and it remained strongly elevated (over fivefold compared to intact LH) for the first 3 days after the LH surge, moderately elevated (over threefold) thereafter until day + 5, and mildly elevated until day + 7.
Total and non-intact LH-ir are potential add-on characteristics which can be utilized in ovulation predictor kits to measure LH-ir in urine beyond the LH surge during a broader time frame, thereby paving the way for more precise prediction of the timing of ovulation than that obtained with currently available products.
在我们之前的研究中，我们通过凝胶过滤分离了三种不同的尿 LH-ir（U-LH-ir）分子形式，并在排卵日的正常月经妇女的尿液中通过免疫测定对其进行了鉴定。U-LH-ir 由完整的促黄体生成激素（LH）、其游离β亚基（LHβ）和 LHβ 核心片段（LHβcf）组成，后两者构成了 LH-ir 的非完整部分。目的是确定通过检测育龄妇女不同形式的 U-LH-ir 是否可以改善排卵时间。
我们在月经周期中连续的排卵日期间测定了 14 名正常月经妇女的完整和总 U-LH-ir。非完整 LH-ir 通过总 LH-ir 和完整 LH-ir 的算术差来计算。此外，我们还在月经周期的 4 名妇女的血清和尿液中测定了 LH-ir。
在 LH 激增期间，U-LH-ir 主要由完整的 LH 组成，并呈现出突然增加。激增后 1 天内，完整的 U-LH-ir 迅速下降，在黄体期结束时达到基线水平。相比之下，尿液中的 LHβcf 在激增后又增加了 1 天。此后，大多数 U-LH-ir 由 LHβcf 组成，并且在 LH 激增后第 1 天至第 3 天内仍保持强烈升高（与完整的 LH 相比升高五倍以上），此后适度升高（升高三倍以上）直至第 5 天，轻度升高直至第 7 天。
总 LH-ir 和非完整 LH-ir 是潜在的附加特征，可在排卵预测试剂盒中用于在更广泛的时间范围内测量尿液中的 LH-ir，超过 LH 激增，从而为更准确地预测排卵时间铺平道路比目前可用产品获得的时间。
