Ishiwata K, Ido T, Kawashima K, Yamada H, Takahashi T, Iwata R, Matsui A, Sakuragawa N
Int J Nucl Med Biol. 1985;12(1):33-6. doi: 10.1016/0047-0740(85)90009-9.
Experimental studies on the biodistribution and placental transfer of in vivo metabolic constituents in pregnant rats were investigated with positron-emitting compounds such as 18F-2-fluoro-2-deoxyglucose, a mixture of 11C-glucose and 11C-fructose, 11C-L-methionine, 11C-D,L-leucine, 11C-adenine, 18F-5-fluoro-2'-deoxyuridine, 11C-S-adenosyl-L-methionine and 11C-coenzyme Q10. Sugars and amino acids transferred easily through the placenta and distributed into the fetal tissues to a similar extent as into the maternal tissues. The fetus-to-placenta ratios for the amino acids were always over 1.0, which indicated active transport of the amino acids in the placenta. On the contrary, other compounds have some limitation to transfer through the placenta in comparison with the sugars and amino acids. The fetus-to-placenta ratios of 11C-adenine, 11C-S-adenosyl-L-methionine and 11C-coenzyme Q10 were much less than the placenta-to-blood ratios, which indicated the presence of a certain placental barrier against these compounds. 11C-S-adenosyl-L-methionine and 11C-coenzyme Q10 were incorporated more into the fetal brain than into the maternal brain which is probably due to the nutritional requirement of the fetal brain and/or an immature blood-brain barrier.
利用正电子发射化合物，如18F - 2 - 氟 - 2 - 脱氧葡萄糖、11C - 葡萄糖与11C - 果糖的混合物、11C - L - 蛋氨酸、11C - D,L - 亮氨酸、11C - 腺嘌呤、18F - 5 - 氟 - 2'- 脱氧尿苷、11C - S - 腺苷 - L - 蛋氨酸和11C - 辅酶Q10，对怀孕大鼠体内代谢成分的生物分布和胎盘转运进行了实验研究。糖类和氨基酸容易通过胎盘转运，并在胎儿组织中的分布程度与母体组织相似。氨基酸的胎儿与胎盘比值始终大于1.0，这表明氨基酸在胎盘中存在主动转运。相反，与糖类和氨基酸相比，其他化合物通过胎盘转运存在一定限制。11C - 腺嘌呤、11C - S - 腺苷 - L - 蛋氨酸和11C - 辅酶Q10的胎儿与胎盘比值远低于胎盘与血液比值，这表明胎盘对这些化合物存在一定屏障。11C - S - 腺苷 - L - 蛋氨酸和11C - 辅酶Q10在胎儿脑中的掺入量比母体脑中更多，这可能是由于胎儿脑的营养需求和/或未成熟的血脑屏障所致。
