Fernstrom M H, Volk E A, Fernstrom J D
Am J Physiol. 1986 Oct;251(4 Pt 1):E393-9. doi: 10.1152/ajpendo.1986.251.4.E393.
The uptake of tyrosine into rat retina and brain was studied in vivo after its peripheral injection alone or in combination with other amino acids. Both retinal and brain tyrosine levels increased monotonically for at least 60 min after tyrosine administration. When tyrosine was injected along with branched-chain amino acids, but not with acidic amino acids, such increments in retinal and brain tyrosine levels were significantly attenuated. The postinjection tyrosine levels in retina and brain paralleled better the serum ratio of tyrosine to the sum of the other large neutral amino acids (which include the branched-chain amino acids) than the serum tyrosine level alone. These results suggest that tyrosine uptake into rat retina, like that into brain, is mediated by a competitive transport system shared among the large neutral amino acids.
单独或与其他氨基酸联合外周注射酪氨酸后，在体内研究了酪氨酸在大鼠视网膜和脑中的摄取情况。给予酪氨酸后，视网膜和脑内的酪氨酸水平至少在60分钟内单调增加。当酪氨酸与支链氨基酸一起注射时，而非与酸性氨基酸一起注射时，视网膜和脑内酪氨酸水平的这种增加会显著减弱。视网膜和脑内注射后酪氨酸水平与血清中酪氨酸与其他大中性氨基酸（包括支链氨基酸）总和的比值的平行关系，比单独的血清酪氨酸水平更好。这些结果表明，大鼠视网膜对酪氨酸的摄取，与脑内一样，是由大中性氨基酸共享的竞争性转运系统介导的。
