Relaxin increases the accumulation of new epithelial and stromal cells in the rat cervix during the second half of pregnancy
Relaxin increases the accumulation of new epithelial and stromal cells in the rat cervix during the second half of pregnancy
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DOI：
10.1210/en.139.9.3984
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发表时间：
1998-09-01
期刊：
影响因子：
4.8
通讯作者：
Sherwood, OD
中科院分区：
文献类型：
--
作者：
Burger, LL;Sherwood, OD
子宫颈和阴道的生长在大鼠妊娠期间都依赖于松弛素。我们最近报道了松弛素依赖性宫颈和阴道DNA含量增加1.5倍，从怀孕中期到足月。这一发现表明松弛素可能至少部分通过促进细胞增殖来促进宫颈和阴道生长。本研究的目的是确定和量化细胞在子宫颈和阴道，增殖在下半年的大鼠妊娠relaxin.Primiparous妊娠大鼠卵巢切除或假卵巢切除（C组; n = 8）在第9天的妊娠（D9）。然后用生理剂量的孕酮加雌激素（n = 7）或孕酮、雌激素和猪松弛素（n = 7）处理卵巢切除大鼠。通过从D9-D22经由微型渗透泵连续施用低剂量的5-溴-2 '-脱氧尿苷（BrdU）来测定细胞增殖。在D22，收集宫颈和阴道，固定在福尔马林中，石蜡包埋，并连续切片（4 μ m）。相邻连续切片进行BrdU免疫染色以评估细胞增殖或用苏木精染色以确定总细胞数。通过计数相邻切片上相同区域中的BrdU阳性核和总核来评价细胞增殖。在X575用计算机数字化形态计量分析测定细胞计数。在对照组大鼠中，近75%的上皮细胞和55%的基质细胞在妊娠后半期增殖。大约一半的新细胞的积累是松弛素依赖性的。在子宫颈基质中，松弛素增加了与血管相关的细胞的积累，也增加了分离细胞（可能是成纤维细胞）的数量。松弛素似乎没有影响cenix平滑肌细胞增殖。与子宫颈相反，少数阴道上皮细胞（45%）和基质细胞（20%）在妊娠后半期增殖。虽然松弛素似乎有增加新的阴道上皮细胞和基质细胞的积累的趋势，形态分析没有提供支持这样的effect.In结论，这项研究表明，松弛素促进宫颈内的新的上皮细胞和基质细胞的积累显着增加。松弛素诱导的新生上皮细胞和基质细胞的增加可能有助于松弛素对快速安全分娩所需的宫颈生长和重塑的影响。
Both cervical and vaginal growth are relaxin dependent during rat pregnancy. We recently reported a relaxin-dependent 1.5-fold increase in cervical and vaginal DNA content from midpregnancy until term. This finding indicated that relaxin probably promotes cervical and vaginal growth at least in part by promoting cellular proliferation. The objective of this study was to identify and quantify cells in the cervix and vagina that proliferate during the second half of rat pregnancy in response to relaxin.Primiparous pregnant rats were ovariectomized or sham ovariectomized (group C; n = 8) on day 9 of pregnancy (D9). Ovariectomized rats mere then treated with physiological doses of progesterone plus estrogen (n = 7) or progesterone, estrogen, and porcine relaxin (n = 7). Cellular proliferation was determined by continuously administering a low dose of 5-bromo-2'-deoxyuridine (BrdU) via miniature osmotic pump from D9-D22. On D22, cervices and vaginas were collected, fixed in formalin, paraffin embedded, and serially sectioned (4 mu m) Adjacent serial sections were either immunostained for BrdU to assess cell proliferation or stained with hematoxylin to determine total cell number. Cell proliferation was evaluated by counting BrdU-positive nuclei and total nuclei in the same area on adjacent sections. Cell counts were determined using computerized digital morphometric analysis at X575.In control rats, nearly 75% of the epithelial cells and 55% of the stromal cells within the cenix at term had proliferated during the second half of pregnancy. The accumulation of approximately half of the new cells was relaxin dependent. Within the cervical stroma, relaxin increased the accumulation of cells associated with blood vessels and also the number of isolated cells (probably fibroblasts). Relaxin did not appear to affect smooth muscle cell proliferation in the cenix. In contrast to the cervix, a minority of vaginal epithelial cells (45%) and stromal cells (20%) proliferated during the second half of pregnancy. Although relaxin appeared to have a tendency to increase the accumulation of new vaginal epithelial and stromal cells, morphometric analysis did not provide support for such an effect.In conclusion, this study demonstrates that relaxin promotes a marked increase in the accumulation of new epithelial cells and stromal cells within the cervix. The relaxin-induced increase in new epithelial and stromal cells probably contributes to relaxin's effects on growth and remodeling of the cervix that are required for rapid and safe delivery.