Hickey G J, Walton J S, Hansel W
Department of Physiology, New York State College of Veterinary Medicine, Cornell University, Ithaca 14853.
J Reprod Fertil Suppl. 1989;37:29-35.
Allantoic fluids (n = 65) of Day 24-37 bovine conceptuses were collected and assayed for luteotrophic activity in vitro with dispersed bovine luteal cells. Significant luteotrophic activity was found in 41% of the samples, with the highest percentage occurring between Days 25 and 28. The activity is ammonium sulphate-precipitable, heat-labile and inactivated by trypsin and chymotrypsin. Gel filtration column chromatography identified one peak of luteotrophic activity with a molecular weight of 68,000. Concanavalin A bound the luteotrophic activity, thus allowing rapid and substantial purification from a major protein of Mr 68,000 which was concanavalin A non-reactive. The results of one- and two-dimensional SDS-PAGE of concanavalin A-reactive fractions containing activity suggest that the luteotrophic activity present in allantoic fluid is associated with a glycoprotein of Mr 68,000 present in very low concentrations. The active factor does not appear to be alpha-fetoprotein. This protein may be an important conceptus-derived luteotrophin that stimulates progesterone production by the corpus luteum of cows during pregnancy.
收集了第24至37天牛胚胎的尿囊液（n = 65），并在体外与分散的牛黄体细胞一起检测其促黄体活性。在41%的样本中发现了显著的促黄体活性，其中最高比例出现在第25至28天之间。该活性可被硫酸铵沉淀、对热不稳定，且能被胰蛋白酶和糜蛋白酶灭活。凝胶过滤柱层析鉴定出一个促黄体活性峰，其分子量为68,000。伴刀豆球蛋白A结合促黄体活性，从而允许从一种分子量为68,000且不与伴刀豆球蛋白A反应的主要蛋白质中快速大量纯化。对含有活性的伴刀豆球蛋白A反应性组分进行一维和二维SDS-PAGE的结果表明，尿囊液中存在的促黄体活性与一种浓度极低的分子量为68,000的糖蛋白有关。该活性因子似乎不是甲胎蛋白。这种蛋白质可能是一种重要的胚胎来源的促黄体素，在怀孕期间刺激奶牛黄体产生孕酮。
