Ortolano G A, Haisenleder D J, Dalkin A C, Iliff-Sizemore S A, Landefeld T D, Maurer R A, Marshall J C
Department of Internal Medicine, University of Michigan, Ann Arbor 48109.
Endocrinology. 1988 Oct;123(4):2149-51. doi: 10.1210/endo-123-4-2149.
Serum follicle-stimulating hormone (FSH), pituitary FSH content and FSH beta subunit mRNA concentrations were measured at 1 to 3h intervals throughout the 4 day estrous cycle in rats. Serum FSH was stable (range 200-320 ng/ml) apart from the biphasic proestrus surge (5 fold elevation) which was present from 1800 h of proestrus through 0800 h on estrus. Basal FSH beta mRNA concentrations from late metestrus through the afternoon of proestrus were 0.10 +/- 0.04 f mol cDNA bound/100 micrograms pituitary DNA. The major increase in FSH beta mRNA began at 2000 h on proestrus, 2 h after the initial rise in serum FSH and peak mRNA concentrations (0.43 +/- 0.08 f mol cDNA bound) occurred at 0200 h on estrus. FSH beta subunit mRNA concentrations were again increased at 2300 h on estrus (peak 0.24 f mol cDNA bound) and remained elevated through 1700 h on metestrus. Pituitary FSH content was transiently increased during metestrus and diestrus, but was elevated at 1000 h through 1900 h on proestrus (peak 5-fold increase). FSH content fell rapidly at 2000 h and remained low until 1400 h on estrus when values again rose. These data show that FSH beta mRNA is increased 4-5 fold during the proestrus FSH surge, and a smaller increase occurs on metestrus in the absence of elevated FSH secretion. The increased concentrations of FSH beta mRNA occurred at different times to the previously reported changes in alpha and LH beta mRNAs. Therefore, the data suggest that different mechanisms are involved in the regulation of LH and FSH beta subunit gene expression during the 4-day estrous cycle in rats.
在大鼠4天的发情周期中，每隔1至3小时测量血清卵泡刺激素（FSH）、垂体FSH含量及FSHβ亚基mRNA浓度。除了发情前期的双相峰（升高5倍）外，血清FSH保持稳定（范围为200 - 320 ng/ml），该双相峰出现在发情前期18:00至发情期08:00。从发情后期到发情前期下午，基础FSHβ mRNA浓度为每100微克垂体DNA结合0.10±0.04 fmol cDNA。FSHβ mRNA的主要增加始于发情前期20:00，在血清FSH最初升高后2小时，发情期02:00出现mRNA浓度峰值（0.43±0.08 fmol cDNA结合）。发情期23:00时FSHβ亚基mRNA浓度再次升高（峰值为0.24 fmol cDNA结合），并在发情后期17:00之前一直保持升高。垂体FSH含量在发情后期和间情期短暂增加，但在发情前期10:00至19:00升高（峰值增加5倍）。FSH含量在20:00迅速下降，并一直保持低水平，直到发情期14:00时再次升高。这些数据表明，在发情前期FSH峰期间FSHβ mRNA增加4 - 5倍，在间情期FSH分泌未升高时也有较小幅度增加。FSHβ mRNA浓度增加的时间与先前报道的α和LHβ mRNA变化时间不同。因此，数据表明在大鼠4天发情周期中，LH和FSHβ亚基基因表达的调控涉及不同机制。
