Jablonka-Shariff A, Grazul-Bilska A T, Redmer D A, Reynolds L P
Department of Animal and Range Sciences, North Dakota State Univ., Fargo 58105, USA.
Growth Factors. 1997;14(1):15-23. doi: 10.3109/08977199709021507.
To determine the relationship between cellular proliferation and the presence of FGF-1 and FGF-2 in the ovine corpus luteum (CL) during early pregnancy, ewes received an intravenous injection of bromodeoxyuridine (BrdU) 1 h before slaughter (n = 3/day) on day 12 after estrus (nonpregnant) or on days 12, 18, 24 or 30 after mating (pregnant). The labeling index (LI; number of BrdU-labeled nuclei expressed as a percentage of total nuclei) of each CL was determined by immunohistochemistry and subsequent image analysis. FGF-1 and FGF-2 were immunolocalized by using specific antibodies, and indirect immunoperoxidase detection. Moreover, FGF-2 was immunolocalized by using a primary antibody and fluorescein isothiocyanate (FITC)-labeled secondary antibody, and immunofluorescence was quantified by using an interactive laser cytometer and image analysis. Results demonstrated that the LI was similar for CL of nonpregnant and pregnant ewes on day 12 (4.27 +/- 0.23 vs 5.10 +/- 0.14%) and decreased (P < 0.05) from days 12-30 of pregnancy (2.73 +/- 0.08, 2.02 +/- 0.09 and 1.70 +/- 0.04% on days 18, 24 and 30, respectively). FGF-1 was present in the cytoplasm of large and a few small parenchymal luteal cells, and the distribution and intensity of staining was similar for nonpregnant and pregnant ewes on day 12 as well as across days of pregnancy. In contrast, FGF-2 immunoreactivity was present only in luteal nonparenchymal cells and interstitial areas and was greater (P < 0.05) for pregnant than nonpregnant CL on day 12 (2.34 +/- 0.12 vs 0.14 +/- 0.01%). Although FGF-2 immunoreactivity decreased (P < 0.01) from days 12-30 of pregnancy (0.70 +/- 0.04, 0.22 +/- 0.01 and 0.06 +/- 0.02% on days 18, 24, and 30, respectively), it was highly correlated (r = 0.99, P < 0.01) with luteal LI. We therefore suggest that FGF, and especially FGF-2, play a role in luteal cell proliferation or turnover during early pregnancy, and may thereby contribute to the maintenance of luteal function, which is critical for the successful establishment of pregnancy.
为了确定妊娠早期绵羊黄体（CL）中细胞增殖与成纤维细胞生长因子-1（FGF-1）和成纤维细胞生长因子-2（FGF-2）存在之间的关系，在发情后第12天（未妊娠）或配种后第12、18、24或30天（妊娠），在屠宰前1小时给母羊静脉注射溴脱氧尿苷（BrdU）（n = 3只/天）。通过免疫组织化学和随后的图像分析确定每个CL的标记指数（LI；BrdU标记核的数量表示为总核的百分比）。使用特异性抗体通过间接免疫过氧化物酶检测对FGF-1和FGF-2进行免疫定位。此外，使用一抗和异硫氰酸荧光素（FITC）标记的二抗对FGF-2进行免疫定位，并使用交互式激光细胞仪和图像分析对免疫荧光进行定量。结果表明，未妊娠和妊娠母羊在第12天的CL的LI相似（4.27±0.23对5.10±0.14%），并且在妊娠第12 - 30天下降（P < 0.05）（在第18、24和30天分别为2.73±0.08、2.02±0.09和1.70±0.04%）。FGF-1存在于大的和一些小的实质黄体细胞的细胞质中，并且在第12天未妊娠和妊娠母羊以及整个妊娠期间的染色分布和强度相似。相比之下，FGF-2免疫反应性仅存在于黄体非实质细胞和间质区域，并且在第12天妊娠CL比未妊娠CL更强（P < 0.05）（2.34±0.12对0.14±0.01%）。尽管FGF-2免疫反应性在妊娠第12 - 30天下降（P < 0.01）（在第18、24和30天分别为0.70±0.04、0.22±0.01和0.06±0.02%），但它与黄体LI高度相关（r = 0.99，P < 0.01）。因此，我们认为FGF，尤其是FGF-2，在妊娠早期黄体细胞增殖或更新中起作用，从而可能有助于维持黄体功能，这对成功建立妊娠至关重要。
