Mori S, Yamaguchi M
Department of Environmental Biochemistry and Toxicology, School of Pharmaceutical Sciences, University of Shizuoka, Japan.
Chem Pharm Bull (Tokyo). 1990 Aug;38(8):2216-8. doi: 10.1248/cpb.38.2216.
The effect of regucalcin, a calcium-binding protein isolated from rat liver cytosol, on cytosolic Ca2+/calmodulin-dependent protein kinase activity was investigated. The increase in cytosolic Ca2+/calmodulin-dependent protein kinase activity with passage of incubation time was clearly prevented by the presence of regucalcin (1.0 microM). An appreciable effect of regucalcin was seen at 0.5 microM. The cytosolic Ca2+/calmodulin-dependent protein kinase activity was fairly increased by increasing concentrations of added Ca2+ (0.25-1.0 mM). This increase was clearly blocked by the presence of regucalcin (1.0 microM). The inhibitory effect of regucalcin on the protein kinase activity was also seen with varying concentrations of calmodulin (2.5-15 micrograms). In the presence of regucalcin (1.0 microM), trifluoperazine (50 microM), an antagonist of calmodulin, significantly decreased the cytosolic Ca2+/calmodulin-dependent protein kinase activity. These results suggest that regucalcin can regulate the Ca2(+)-calmodulin effect in liver cytosol.
研究了从大鼠肝细胞溶质中分离得到的钙结合蛋白调钙素对胞质Ca2+/钙调蛋白依赖性蛋白激酶活性的影响。调钙素（1.0微摩尔）的存在明显抑制了随着孵育时间延长胞质Ca2+/钙调蛋白依赖性蛋白激酶活性的增加。在0.5微摩尔时可观察到调钙素的显著作用。添加的Ca2+（0.25 - 1.0毫摩尔）浓度增加时，胞质Ca2+/钙调蛋白依赖性蛋白激酶活性显著增加。调钙素（1.0微摩尔）的存在明显阻断了这种增加。调钙素对蛋白激酶活性的抑制作用在不同浓度的钙调蛋白（2.5 - 15微克）下也可见到。在调钙素（1.0微摩尔）存在的情况下，钙调蛋白拮抗剂三氟拉嗪（50微摩尔）显著降低了胞质Ca2+/钙调蛋白依赖性蛋白激酶活性。这些结果表明，调钙素可以调节肝细胞溶质中的Ca2+ - 钙调蛋白效应。
