Changes in progesterone receptor levels during deciduomata development in the pseudopregnant rat.
Changes in progesterone receptor levels during deciduomata development in the pseudopregnant rat.
复制标题
假孕大鼠蜕膜发育过程中黄体酮受体水平的变化。
作者：
E. G. Armstrong;J. Tobert;D. Talley;C. Villee
一个特定的细胞质孕酮受体已被确定和定量蜕膜的假孕大鼠。该受体在蔗糖密度梯度上的沉降系数为6-7S，并被蛋白水解酶、巯基封闭剂和升高的温度灭活。孕酮与蜕膜体受体结合的平衡结合常数约为10（9）M-1。在蜕膜化的第3天和第5天，从蜕膜瘤制备的细胞质中孕酮受体位点的浓度分别为3.4 +/- 0.3 × 10（-10）M和3.6 +/- 0.4 × 10（10）M，当标准化为1 mg/ml的蛋白质浓度时。这些浓度的孕激素受体网站是相似的，在子宫胞液中测得的发情大鼠或在对侧未处理的子宫角的大鼠进行蜕膜化。第5天的蜕膜化后，孕酮受体位点的浓度呈线性下降，因此，到第7天，浓度约为第3天和第5天的一半。孕激素受体的生理意义和其浓度随时间的减少进行了讨论，就其对蜕膜化反应的影响。
A specific cytoplasmic progesterone receptor has been identified and quantified in the deciduomata of the pseudopregnant rat. The receptor had a sedimentation coefficient of 6-7S on sucrose density gradients and was inactivated by proteolytic enzymes, sulfhydryl blocking agents and elevated temperature. The equilibrium association constant for the binding of progesterone by the deciduomal receptor was determined to be approximately 10(9)M-1. The concentrations of progesterone receptor sites in cytosols prepared from deciduomata on day 3 and 5 of decidualization were 3.4 +/- 0.3 X 10(-10)M and 3.6 +/- 0.4 X 10(10)M, respectively, when normalized to a protein concentration of 1 mg/ml. These concentrations of progesterone receptor sites were similar to that measured in the uterine cytosol of estrous rats or in the contralateral untreated uterine horn of rats undergoing decidualization. Following day 5 of decidualization the concentrations of progesterone receptor sites decreased linearly so that by day 7 the concentration was approximately one-half that at days 3 and 5. The physiological significance of the progesterone receptor and the decrease in its concentration with time are discussed with regard to their influence on the decidualization reaction.