Inpanbutr N, Miller E K, Petroff B K, Iacopino A M
Department of Veterinary Anatomy and Cellular Biology, Ohio State University College of Veterinary Medicine, Columbus 43210.
Biol Reprod. 1994 Mar;50(3):561-71. doi: 10.1095/biolreprod50.3.561.
The expression of calbindin-D9K (CaBP9K) and calbindin-D28K (CaBP28K) genes in the reproductive system is well established for rodent and avian species, but not for domestic livestock. This investigation expanded the study of these proteins to include the bovine uterus and examined the levels of CaBP9K and CaBP9K mRNA in the nonpregnant bovine uterus during the estrous cycle. Immunohistochemical studies revealed that CaBP9K was present in all uterine glandular and luminal epithelial cells. In contrast, the closely related calcium binding protein CaBP28K was present in only one to two glandular cells in the samples examined. Neither protein was localized in the myometrium or in the stromal cells of the endometrium. RIA and dot blot hybridization were used to quantify the amount of CaBP9K and CaBP9K mRNA. The levels of both the protein and its mRNA were threefold higher during the luteal phase than during the follicular phase. RIA was also used to determine bovine uterine levels of 17 beta-estradiol and progesterone. Progesterone levels were higher during the luteal phase than during the follicular phase, while 17 beta-estradiol levels were higher during the follicular phase. This investigation represents the first characterization of CaBP9K gene expression in the bovine uterus. It demonstrated that the expression of CaBP9K and CaBP9K mRNA was greatest during the progesterone-dominated luteal phase of the bovine estrous cycle. These results indicated that CaBP9K may be involved in uterine glandular function during the luteal phase.
钙结合蛋白-D9K（CaBP9K）和钙结合蛋白-D28K（CaBP28K）基因在啮齿动物和鸟类生殖系统中的表达已得到充分证实，但在家畜中尚未得到证实。本研究将这些蛋白质的研究扩展到家牛子宫，并检测了发情周期中未怀孕牛子宫中CaBP9K和CaBP9K mRNA的水平。免疫组织化学研究表明，CaBP9K存在于所有子宫腺上皮和腔上皮细胞中。相比之下，在所检测的样本中，密切相关的钙结合蛋白CaBP28K仅存在于一到两个腺细胞中。两种蛋白质均未定位在子宫肌层或子宫内膜的基质细胞中。采用放射免疫分析（RIA）和斑点印迹杂交法对CaBP9K和CaBP9K mRNA的含量进行定量。黄体期蛋白质及其mRNA的水平比卵泡期高三倍。RIA还用于测定牛子宫中17β-雌二醇和孕酮的水平。黄体期孕酮水平高于卵泡期，而卵泡期17β-雌二醇水平较高。本研究首次对牛子宫中CaBP9K基因表达进行了表征。结果表明，在牛发情周期中以孕酮为主的黄体期，CaBP9K和CaBP9K mRNA的表达最高。这些结果表明，CaBP9K可能在黄体期参与子宫腺功能。
