Sidorkina O M, Morozova T M, Rau V A
Biokhimiia. 1988 Mar;53(3):406-12.
The effect of 17 beta-estradiol on protein kinase C in target cells was studied. It was shown that 10-15 min after injection of ovariectomized animals with estradiol (10 micrograms intraperitoneally) protein kinase C is translocated from the cytosol into the cell membranes of estradiol-dependent mammary gland tumours. A similar effect of estradiol on protein kinase C is observed in uterine tissue. On the contrast, in hormone-independent rat mammary gland tumours estradiol causes no redistribution of protein kinase C between the cytosol and cell membranes. No protein kinase C accumulation in the membranes of hormone-dependent mammary gland tumours is observed 30 min after estradiol injection. However, this period is characterized by the appearance of protein kinase whose activity is not stimulated by Ca2+ or phosphatidylserine and which is eluted from DEAE-cellulose with 0.2 M NaCl. This protein kinase presumably corresponds to the M-fragment, i.e., the catalytic part of protein kinase C formed as a result of protein kinase C proteolysis on the membranes. It seems likely that estradiol, similar to growth factor peptides, realizes its stimulating effect on cell division primarily at the expense of coupling of its membrane receptors with the protein kinase C activation system.
研究了17β-雌二醇对靶细胞中蛋白激酶C的影响。结果表明，给去卵巢动物腹腔注射雌二醇（10微克）后10 - 15分钟，蛋白激酶C从胞质溶胶转移至依赖雌二醇的乳腺肿瘤细胞膜。在子宫组织中也观察到雌二醇对蛋白激酶C有类似作用。相反，在激素非依赖性大鼠乳腺肿瘤中，雌二醇不会引起蛋白激酶C在胞质溶胶和细胞膜之间的重新分布。注射雌二醇30分钟后，未观察到依赖激素的乳腺肿瘤细胞膜中有蛋白激酶C积累。然而，此阶段的特征是出现一种蛋白激酶，其活性不受Ca2+或磷脂酰丝氨酸刺激，且能用0.2M NaCl从DEAE - 纤维素上洗脱下来。这种蛋白激酶可能对应于M片段，即蛋白激酶C在膜上经蛋白水解形成的催化部分。雌二醇似乎与生长因子肽类似，主要通过其膜受体与蛋白激酶C激活系统的偶联来实现对细胞分裂的刺激作用。
