Joëls Marian
Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, 1098 SM Amsterdam, The Netherlands.
Trends Pharmacol Sci. 2006 May;27(5):244-50. doi: 10.1016/j.tips.2006.03.007. Epub 2006 Apr 3.
The existence of U-shaped dose dependencies has been known for a long time. With regard to corticosteroid action in brain cells, a dual receptor system that works in opposing directions can explain the occurrence of a U-shaped dose dependency. However, recent evidence indicates that many cell- and tissue-specific factors (e.g. the local availability of corticosterone, the expression of receptor variants and the cellular content of other proteins and molecules) also determine the effectiveness of the hormone. This could result in dose dependencies with a different shape, despite the local presence of two receptor types.
U型剂量依赖性的存在已为人所知许久。关于皮质类固醇在脑细胞中的作用，一个以相反方向起作用的双受体系统可以解释U型剂量依赖性的出现。然而，最近的证据表明，许多细胞和组织特异性因素（例如皮质酮的局部可用性、受体变体的表达以及其他蛋白质和分子的细胞含量）也决定了该激素的有效性。尽管局部存在两种受体类型，但这可能导致具有不同形状的剂量依赖性。
