Wapnir R A, Gyasi I, Harper R G, Moyse J, Teichberg S
Department of Pediatrics, North Shore University Hospital-New York University School of Medicine, Manhasset 11030, USA.
Placenta. 1996 Sep;17(7):479-86. doi: 10.1016/s0143-4004(96)90030-2.
Copper (Cu) placental transport presents a steep downhill gradient from mother to fetus. This process could be altered by low-molecular-weight (LMW) ligands and maternal Cu deficiency. We compared the ratio of Cu transfer from dam-to-fetus in Cu-deficient (CuDf) and Cu-sufficient (CuSf) rats in the last day of gestation. Anaesthetized dams were iv injected 79 mumol/kg (5 mg/kg) of either Cu acetate [Cu (AcO)2]; Cu+L-histidine, 1:10. [Cu(His)10]; Cu-(glycyl-glycyl-L-histidine) [Cu(GGH)], or saline. Dam and fetal blood, as well as placentae were obtained at 0, 10, 20, 40 and 60 min. At time 0, CuDf dams had lower plasma Cu than CuSf dams (8.3 +/- 1.2 versus 26.7 +/- 1.1 mumol/l), but CuDf fetuses plasma Cu was unchanged. This resulted in a more favourable mean fetal: maternal plasma Cu ratio in the CuDf fetuses (0.61) than in the CuSf fetuses (0.21). Dam plasma Cu was unaffected by the chemical form of Cu injected. In CuDf fetuses lower plasma Cu was observed with Cu(GGH) and Cu (His)10 at 20 min than in the CuSf. In the presence of these LMW ligands CuDf placentae retained more Cu than those of the CuSf group. CuDf was associated ultrastructurally with extensive lipid deposition in dam hepatocytes and, to a lesser extent, in CuDf fetal liver. These results indicate that in CuDf, LMW ligands increase placental uptake of Cu, without improving placenta-fetus transport. Although the rat fetus is well adapted to intrauterine CuDf, it may also be susceptible to hepatic lipid infiltration when the dam is CuDf.
铜（Cu）的胎盘转运呈现出从母体到胎儿的陡峭下坡梯度。这个过程可能会受到低分子量（LMW）配体和母体铜缺乏的影响。我们比较了妊娠最后一天铜缺乏（CuDf）和铜充足（CuSf）大鼠中从母体到胎儿的铜转运比例。对麻醉的母鼠静脉注射79 μmol/kg（5 mg/kg）的醋酸铜[Cu(AcO)₂]；铜与L-组氨酸，1:10[Cu(His)₁₀]；铜-(甘氨酰-甘氨酰-L-组氨酸)[Cu(GGH)]，或生理盐水。在0、10、20、40和60分钟时获取母鼠和胎儿的血液以及胎盘。在时间0时，CuDf母鼠的血浆铜低于CuSf母鼠（8.3±1.2对26.7±1.1 μmol/L），但CuDf胎儿的血浆铜没有变化。这导致CuDf胎儿的平均胎儿：母体血浆铜比例（0.61）比CuSf胎儿（0.21）更有利。母鼠血浆铜不受注射铜的化学形式的影响。在CuDf胎儿中，在20分钟时观察到与CuSf相比，Cu(GGH)和Cu(His)₁₀导致血浆铜更低。在这些LMW配体存在的情况下，CuDf胎盘比CuSf组的胎盘保留了更多的铜。超微结构显示CuDf与母鼠肝细胞中广泛的脂质沉积有关，在较小程度上也与CuDf胎儿肝脏中的脂质沉积有关。这些结果表明，在CuDf中，LMW配体增加了胎盘对铜的摄取，但没有改善胎盘-胎儿的转运。尽管大鼠胎儿对子宫内的CuDf有很好的适应性，但当母鼠铜缺乏时，它也可能易患肝脏脂质浸润。
