Testosterone transport in brain: primary role of plasma protein-bound hormone.
Testosterone transport in brain: primary role of plasma protein-bound hormone.
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睾酮在大脑中的转运：血浆蛋白结合激素的主要作用。
DOI：
10.1152/ajpendo.1985.249.5.e534
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Landaw,EM
中科院分区：
文献类型：
--
作者：
Pardridge,WM;Landaw,EM
基于生理学的数学模型用于预测大脑中细胞内游离和结合睾酮的稳态浓度。根据先前对大鼠体内睾酮从血液到大脑和从大脑到血液转运的体内示踪动力学研究，将值分配给各种生理参数（激素与血浆和胞质结合蛋白的结合和解离反应、毛细血管通过时间和膜转运）。该模型不遵守游离激素假说的限制，并允许增强激素从血浆蛋白结合库到组织血管外空间的转运。据信该过程是通过配体与血浆蛋白结合的内皮抑制而发生的，而蛋白不穿过内皮壁。该模型预测细胞内游离激素的稳态浓度变化与体外测量的血浆蛋白结合激素浓度的变化更接近，而不是与体外测量的游离激素浓度的变化更接近。
Physiologically based mathematical modeling is used to predict the steady-state concentration of intracellular free and bound testosterone in brain. On the basis of previous in vivo tracer kinetic studies of blood-to-brain and brain-to-blood transport of testosterone in the rat, values are assigned to various physiological parameters (hormone association and dissociation reactions with plasma and cytosolic binding proteins, capillary transit time, and membrane transport). The model does not adhere to the restrictions of the free hormone hypothesis and allows for the enhanced transport of hormone from the plasma protein-bound pool into the tissue extravascular space. This process is believed to occur via an endothelial inhibition of ligand binding to the plasma protein without the protein crossing the endothelial wall. The model predicts that the steady-state concentration of intracellular free hormone changes in parallel more closely to changes in the concentration of plasma protein-bound hormone as measured in vitro and not the free hormone as measured in vitro.