Huether G
Neurochem Res. 1986 Dec;11(12):1663-8. doi: 10.1007/BF00967744.
In suckling hyperphenylalaninemic (hyper-Phe) rats, all essential amino acids including tryptophan are depleted in the blood. The inadequate supply of Trp to the developing brain leads to a decline of Trp, of serotonin, and of 5-hydroxyindoleacetic acid. The exhaustion of amino acids in both blood and brain can be restored by administration of Lys. Even though Phe is still elevated in blood and brain, Trp, serotonin and 5-hydroxyindoleacetic acid, are no longer depleted in the brain. This observation contradicts the idea that the serotonin deficit in the developing hyper-Phe brain is caused by competitive uptake inhibition of tryptophan or by the interference of Phe metabolites with the formation of serotonin. Increased accumulation of all large neutral amino acids in peripheral tissues and an impeded intestinal amino acid transport in suckling hyper-Phe rats appear to be responsible for the deficient supply of other amino acids, including Trp, to the developing brain. The availability of Lys for developing extraintestinal tissues seems to be involved in the regulation of intestinal amino acid transport.
在乳鼠高苯丙氨酸血症（高苯丙氨酸）大鼠中，包括色氨酸在内的所有必需氨基酸在血液中都会减少。色氨酸向发育中的大脑供应不足会导致色氨酸、血清素和5-羟吲哚乙酸减少。通过给予赖氨酸可以恢复血液和大脑中氨基酸的耗尽。尽管血液和大脑中的苯丙氨酸仍然升高，但大脑中的色氨酸、血清素和5-羟吲哚乙酸不再减少。这一观察结果与发育中的高苯丙氨酸大脑中血清素缺乏是由色氨酸的竞争性摄取抑制或苯丙氨酸代谢物对血清素形成的干扰所导致的观点相矛盾。乳鼠高苯丙氨酸血症大鼠外周组织中所有大中性氨基酸的积累增加以及肠道氨基酸转运受阻似乎是发育中的大脑中包括色氨酸在内的其他氨基酸供应不足的原因。赖氨酸对发育中的肠外组织的可用性似乎参与了肠道氨基酸转运的调节。
