L-[2-¹⁸F]氟苯丙氨酸和L-[U-¹⁴C]苯丙氨酸：它们向大鼠脑内转运的比较研究

L-[2-18F]fluorophenylalanine and L-[U-14C]phenylalanine: a comparative study of their transport to rat brain.

作者信息

Nakamichi H, Murakami M, Miura S, Kondoh Y, Mizusawa S, Ono Y

机构信息

Department of Internal Medicine.

出版信息

Nucl Med Biol. 1993 Jan;20(1):95-9. doi: 10.1016/0969-8051(93)90141-g.

DOI:10.1016/0969-8051(93)90141-g

PMID:8461885

Abstract

The transport rates of L-[2-18F]fluorophenylalanine ([18F]Phe) and L-[U-14C]phenylalanine ([14C]Phe) across the blood-brain barrier were compared in saline, large neutral amino acids (NAA) and large basic amino acids (BAA) loaded rats. The fraction of transported tracer (FTT) was expressed as the ratio of brain radioactivity to integrated plasma radioactivity at 5 min after injection of the tracers. Cerebral FTTs of [18F]Phe and [14C]Phe in the control group were 0.042 and 0.045, respectively, and decreased to 0.016 and 0.019 in the NAA loaded group. The ratios of FTT of [18F]Phe and that of [14C]Phe were approx. 0.90, and did not differ among the three groups. These results indicate that the transport of [18F]Phe from the blood to the brain can be considered to be mediated by the NAA transport system and that its transport rate is almost the same as that of [14C]Phe.

摘要

在生理盐水、加载了大中性氨基酸（NAA）和大碱性氨基酸（BAA）的大鼠中，比较了L-[2-¹⁸F]氟苯丙氨酸（[¹⁸F]Phe）和L-[U-¹⁴C]苯丙氨酸（[¹⁴C]Phe）跨越血脑屏障的转运速率。转运示踪剂分数（FTT）表示为注射示踪剂后5分钟时脑放射性与血浆放射性积分的比值。对照组中[¹⁸F]Phe和[¹⁴C]Phe的脑FTT分别为0.042和0.045，在加载NAA的组中降至0.016和0.019。[¹⁸F]Phe的FTT与[¹⁴C]Phe的FTT之比约为0.90，且在三组之间无差异。这些结果表明，[¹⁸F]Phe从血液到脑的转运可被认为是由NAA转运系统介导的，且其转运速率与[¹⁴C]Phe几乎相同。