血浆酪氨酸浓度正常的12名受检者,口服酪氨酸100mg/kg 或者150mg/kg,2～8小时以后明显升高。2小时后血浆酪氨酸浓度平均最高,服100mg/kg 后可升高69±3.9到154±9.5nmols/ml((?)±SEM),服150mg/kg 可达203±31.5nmols/ml(二者(P≤0.001)服100mg/kg 2小时后酪氨酸平均比(即血浆酪氨酸浓度与竞争同一血脑屏障吸收系统的其他6种中性氨基酸之和的比例)从0.10±0.02 Twelve subjects with normal plasma tyrosine concentrations were either orally administered tyrosine 100 mg / kg or 150 mg / kg, significantly elevated after 2-8 hours. After 2 hours, the mean plasma tyrosine concentration was the highest, increasing to 69 ± 3.9 to 154 ± 9.5 nmols / ml (± SEM) after taking 100 mg / kg and up to 203 ± 31.5 nmols / ml for 150 mg / kg The average tyrosine ratio (ie, the ratio of plasma tyrosine concentration to the sum of the other 6 neutral amino acids competing for the same blood-brain barrier absorption system) for both 100 mg / kg 2 hours (P <0.001)