Pollay M
J Neurosci Res. 1976;2(1):11-9. doi: 10.1002/jnr.490020103.
In adult rats, using the single-pass brain uptake technique with a tritiated water standard, L-phenylalanine was shown to enter brain across the blood-brain barrier (BBB) by both a saturable and diffusionary process. A kinetic analysis of the data revealed a Michaelis constant (Ka) of 0.42 mM and a Vmax of 35 nmoles g-1 min-1. The saturable component of L-phenylalanine transport was adversely affected by dinitrophenol or or low sodium concentration in the intracarotid injection solution. Intravascular ouabain did not affect transport and only partial inhibition was observed with 1.5 mM L-leucine. It appears that there is no reginonal difference in the capacity of the BBB to move L-phenylalanine from blood to brain. This process is directly or indirectly coupled to sodium movement and is partially dependent on cellular energy.
在成年大鼠中，采用以氚标记水为标准的单通道脑摄取技术，结果显示L-苯丙氨酸可通过饱和及扩散过程跨越血脑屏障（BBB）进入脑内。对数据进行动力学分析得出，米氏常数（Ka）为0.42 mM，最大反应速度（Vmax）为35纳摩尔·克-1·分钟-1。L-苯丙氨酸转运的饱和成分受到二硝基苯酚或颈内注射溶液中低钠浓度的不利影响。血管内注射哇巴因不影响转运，1.5 mM的L-亮氨酸仅产生部分抑制作用。似乎血脑屏障将L-苯丙氨酸从血液转运至脑内的能力不存在区域差异。此过程直接或间接与钠的转运相关，且部分依赖于细胞能量。
