Concurrent regulation ofcholesterol sulfotransferase and sulfatase

妊娠兔子宫内膜中胆固醇硫酸盐的每克干重浓度增加，妊娠子宫内膜中的胆固醇硫酸盐浓度是非妊娠子宫内膜的140倍。在妊娠兔子宫内膜中，总胆固醇的十分之一被硫酸盐化到最高水平，同时调节胆固醇磺基转移酶和胆固醇硫酸酯酶来提高胆固醇硫酸盐的浓度。硫酸胆固醇的合成存在于子宫内膜上皮细胞中，但不存在于间质细胞中。关于妊娠子宫内膜中胆固醇硫酸盐的诱导机制，细胞密度被发现是重要的。孕酮对稀疏培养的子宫内膜细胞不能诱导胆固醇硫酸盐的诱导，但在与孕酮的融合培养中出现了胆固醇磺基转移酶的激活，这表明子宫内膜细胞对类固醇激素的反应需要细胞在充分的阶段分化。这一发现与兔促性腺激素分泌孕酮4天后子宫内膜中出现了磺基转移酶相吻合，尽管是子宫内膜启动了增殖。角质形成细胞在融合期也有同样的激活。另一方面，发现硫酸胆固醇选择性地分布在消化器官和肾脏的上皮细胞中。虽然肝脏中胆固醇硫转移酶和胆固醇硫酸酯酶的比活力和代谢前体胆固醇的浓度显著升高，但在皮肤的发育过程中观察到了胆固醇硫酸盐和转谷氨酰胺酶的程序性表达。事实上，硫酸胆固醇具有激活蛋白激酶n的特征，并与谷氨酰胺转氨酶的诱导有关。

Cholesterol sulfatein the endometrium of rabbit uterus was increasedin the concentration per gram dry weight by pregnancy, and the concentration in the pregnant endometrium was 140-fold than that in the nonpregnant endometrium. In the endometrium of pregnant rabbit, one tenth of the total cholesterol was sulfated at the maxmum level and both of cholesterol sulfotransferase and cholesterol sulfate sulfatase were simultaneously regulated to elevate the concentration of cholesterol sulfate. Synthesis of cholesterol sulfate was found to occure in the epithelial cells of uterine endometrium, but not in the stromal cells. Concerning on the mechanism of induction of cholesterol sulfate in the pregnant endometrium, the cell density was found to be important. A stimulation with progesterone to the sparce culture of the endometrial cells was unable to induce cholesterol sulfate, but activation of cholesterol sulfotransferase occurred to the confluent culture with progesterone, indicating that responsiveness of the endometrial cells to steroid hormones requires for the cells to differentiate in the sufficient stage. This findings coincided that the sulfotransferase appeared in the endometrium of rabbits 4 days after administration of gonadtropin to secrete progesterone, though the endometrium initiated the proliferation. the same activation was observed in The confluent stage of keratinocytes. On the other hand, cholesterol sulfate was found tobe selectively distributed in the epithelial cells in the digestive organs and kidney. Although the spspecific activities of cholesterol sulfotransferase and cholesterol sulfate sulfatase and the concentration of metabolic precurson cholesterol were significantly high in liver, a programd expression of cholesterol sulfate and transglutaminase was observed during the development of skin. In fact, cholesterol sulfate characteristically activated protein kinase n and was related to the induction of transglutaminase.