Christensen S, Verhage H G, Nowak G, de Lanerolle P, Fleming S, Bell S C, Fazleabas A T, Hild-Petito S
Department of Obstetrics and Gynecology, University of Illinois College of Medicine, Chicago 60612-7313, USA.
Biol Reprod. 1995 Sep;53(3):598-608. doi: 10.1095/biolreprod53.3.598.
The objective of this study was to investigate the localization and hormonal regulation of smooth muscle myosin II (SMM II) and alpha smooth muscle actin (alpha SMA) in the baboon uterus, since cytoskeletal proteins are involved in secretory function and morphological transformation. Uterine tissue was obtained from baboons 1) during the menstrual cycle, 2) following steroid treatment of ovariectomized baboons, 3) during pregnancy (Days 14-60 postovulation [PO]), and 4) during simulated pregnancy (Days 18-32 PO). Tissues were processed for immunocytochemical localization of SMM II or alpha SMA with specific polyclonal or monoclonal antibodies, respectively. SMM II stained all smooth muscle cells of blood vessels and myometrium regardless of treatment. Glandular epithelial staining was present only in endometrium obtained during the luteal phase or following estrogen and progesterone treatment. Staining intensity was greater in the basalis than in the functionalis. The number of glands staining positive for SMM II on Days 18-32 of pregnancy and simulated pregnancy was variable. Glandular stain was absent after Day 32 PO. These immunocytochemical data were confirmed by immunoblot analysis of glandular cytosolic extracts. Stromal staining for SMM II was present under the luminal epithelium during simulated pregnancy (Days 18-32), on Day 25 of steroid treatment in the simulated-pregnant controls, and in nonimplantation sites during pregnancy. In contrast, alpha SMA staining was low or absent in all uterine cell types in ovariectomized baboons. Under estrogen-dominated conditions (follicular phase and estrogen treatment), alpha SMA staining was present in smooth muscle cells, and this staining persisted throughout the remaining treatment periods. Glandular epithelial staining for alpha SMA was absent in all treatment groups. However, alpha SMA staining in stromal fibroblasts underneath the luminal epithelium was evident as early as Day 14 of pregnancy and Day 18 of simulated pregnancy. The number of stromal fibroblasts that stained positive increased in the surface region of the functionalis between Days 18 and 32 PO, and the staining extended throughout the upper functionalis region. There was a decrease in the number of positively stained stromal fibroblasts, particularly at the implantation site, between Days 32 and 40 of pregnancy. By Days 50-60 of pregnancy, this staining was almost absent. The induction of alpha SMA in stromal fibroblasts in the functionalis region in pregnant baboons was confirmed by immunoblot analysis of stromal cell cytosol extracts. We conclude that the progesterone-induced glandular expression of SMM II may be involved in uterine secretory function and that alpha SMA expression in stromal fibroblasts during pregnancy and after long-term steroid treatment is associated with the decidualization process.
本研究的目的是探讨狒狒子宫中平滑肌肌球蛋白II（SMM II）和α平滑肌肌动蛋白（αSMA）的定位及激素调节，因为细胞骨架蛋白参与分泌功能和形态转变。子宫组织取自狒狒：1）在月经周期期间；2）对去卵巢狒狒进行类固醇治疗后；3）在妊娠期间（排卵后[PO]第14 - 60天）；4）在模拟妊娠期间（PO第18 - 32天）。分别用特异性多克隆或单克隆抗体对组织进行处理，以进行SMM II或αSMA的免疫细胞化学定位。无论何种处理，SMM II均对血管和子宫肌层的所有平滑肌细胞染色。腺上皮染色仅出现在黄体期获得的子宫内膜或雌激素和孕激素治疗后的子宫内膜中。基底膜的染色强度大于功能层。妊娠和模拟妊娠第18 - 32天，SMM II染色阳性的腺体数量各不相同。PO第32天后腺上皮无染色。这些免疫细胞化学数据通过对腺细胞胞质提取物的免疫印迹分析得到证实。在模拟妊娠期间（第18 - 32天），在腔上皮下方的基质中有SMM II染色；在模拟妊娠对照组中，类固醇治疗第25天有SMM II染色；在妊娠期间的非着床部位也有SMM II染色。相比之下，去卵巢狒狒的所有子宫细胞类型中αSMA染色较低或无染色。在雌激素占主导的条件下（卵泡期和雌激素治疗），αSMA染色出现在平滑肌细胞中，并且这种染色在其余治疗期间持续存在。所有治疗组的腺上皮均无αSMA染色。然而，早在妊娠第14天和模拟妊娠第18天，腔上皮下方的基质成纤维细胞中就有明显的αSMA染色。在PO第18天至32天之间，功能层表面区域中αSMA染色阳性的基质成纤维细胞数量增加，且染色扩展至整个功能层上部区域。在妊娠第32天至40天之间，尤其是在着床部位，αSMA染色阳性的基质成纤维细胞数量减少。到妊娠第50 - 60天，这种染色几乎消失。通过对基质细胞胞质提取物的免疫印迹分析，证实了妊娠狒狒功能层区域基质成纤维细胞中αSMA的诱导。我们得出结论，孕酮诱导的SMM II在腺上皮中的表达可能参与子宫分泌功能，并且妊娠期间和长期类固醇治疗后基质成纤维细胞中αSMA的表达与蜕膜化过程相关。
