Haack D, Vecsei P
Arzneimittelforschung. 1982;32(8):832-4.
The rate of hydrolysis of different water soluble esters of corticoids was determined with newly developed specific radioimmunoassays in healthy subjects. It can be found, that triamcinoloneacetonide phosphate was significantly faster transformed into free form after i.v. application than the reference substances prednisolone- and methylprednisolone hemisuccinate. Moreover the plasma concentration of free triamcinolone-acetonide decreases much faster than that of free prednisolone and methylprednisolone. This shows, that triamcinoloneacetonide is distributed wider and very quickly, probably in the intracellular fluid volume. At this time it is not clear, whether only free steroids are biologically active or the water soluble derivatives as well. Our results can be of clinical importance because of the different rates of hydrolysis as well as of differences in the diffusion.
在健康受试者中，使用新开发的特异性放射免疫分析法测定了不同皮质类固醇水溶性酯的水解速率。结果发现，静脉注射后，磷酸曲安奈德转化为游离形式的速度明显快于对照物质泼尼松龙和甲泼尼龙半琥珀酸酯。此外，游离曲安奈德的血浆浓度下降速度比游离泼尼松龙和甲泼尼龙快得多。这表明，曲安奈德分布更广泛且速度非常快，可能分布于细胞内液体积中。目前尚不清楚是只有游离类固醇具有生物活性还是水溶性衍生物也具有生物活性。由于水解速率不同以及扩散存在差异，我们的结果可能具有临床重要性。
