Decreases in brain protein synthesis elicited by moderate increases in plasma phenylalanine.
Decreases in brain protein synthesis elicited by moderate increases in plasma phenylalanine.
复制标题
血浆苯丙氨酸适度增加引起脑蛋白质合成减少。
DOI：
10.1016/0006-291x(90)91153-j
复制
发表时间：
1990
影响因子：
3.1
通讯作者：
Pardridge,WM
中科院分区：
文献类型：
--
作者：
Wall,KM;Pardridge,WM
血浆苯丙氨酸浓度的大幅增加（> 1 mM）会对脑功能产生不利影响，并抑制脑蛋白质合成。阈值假说预测血浆苯丙氨酸浓度的适度增加低于1 mM阈值对脑功能或蛋白质合成没有不利影响。使用一种新的原位颈内动脉灌注技术和测量的氨基酰-tRNA的特异性活性的高效液相色谱（HPLC）分离的苯异硫氰酸酯（PITC）衍生的氨基酸，目前的研究表明，在体内的大脑蛋白质合成的线性下降的比例，适度增加血浆苯丙氨酸。在血浆苯丙氨酸浓度约为0.40 mM时，观察到脑蛋白质合成抑制50%。由于血浆苯丙氨酸浓度的适度增加可能会在人类摄入苯丙氨酸时实现，因此在评估自由和选择性增加膳食苯丙氨酸的安全性时应考虑本研究结果。
Large increases in plasma phenylalanine concentration (> 1 mM) adversely affect brain function and inhibit cerebral protein synthesis. The threshold hypothesis predicts that moderate increases in plasma phenylalanine concentrations below a 1 mM threshold have no adverse effects on brain function or protein synthesis. Using a new in situ internal carotid artery perfusion technique and measurement of the amino acyl-tRNA specific activities by high performance liquid chromatography (HPLC) separation of phenylisothiocyanate (PITC) derivatized amino acids, the present studies demonstrate a linear decrease in cerebral protein synthesis in vivo in proportion to moderate increases in plasma phenylalanine. A 50% inhibition of brain protein synthesis in vivo is observed at a plasma phenylalanine concentration of approximately 0.40 mM. Since moderate increases in plasma phenylalanine concentrations may be achieved in humans with ingestion of phenylalanine, the present findings should be considered in evaluating the safety of liberal and selective increases in dietary phenylalanine.