Sherman W R, Munsell L Y, Wong Y H
J Neurochem. 1984 Mar;42(3):880-2. doi: 10.1111/j.1471-4159.1984.tb02765.x.
Twenty hours following the subcutaneous administration of 5 mEq/kg doses of 6LiCl and 7LiCl to two groups of rats, the cerebral cortex molar ratio of 6Li+/7Li+ is 1.5. The effects of the lithium isotopes on cortex myo-inositol and myo-inositol-l-phosphate levels are the same as we have reported earlier: a Li+ concentration-dependent lowering of myo-inositol and increase in myo-inositol-1-phosphate. Thus 6LiCl, when administered at the same dose as 7LiCl, produces the larger effect on inositol metabolism. When the 6LiCl and 7LiCl doses were adjusted to 5 mEq/kg and 7 mEq/kg, respectively, the cortical lithium myo-inositol and myo-inositol-1-phosphate levels of each group of animals became approximately equal, suggesting that the isotope effect occurs at the level of tissue uptake, but not on inositol phosphate metabolism. The inhibition of myo-inositol-1-phosphatase by the two lithium isotopes in vitro showed no differential effect. The isotope effect on cerebral cortex uptake of lithium is in the same direction as that reported by others for erythrocytes and for the CSF/plasma ratio, but of larger magnitude.
给两组大鼠皮下注射5 mEq/kg剂量的6LiCl和7LiCl 20小时后，大脑皮层中6Li+/7Li+的摩尔比为1.5。锂同位素对皮层肌醇和肌醇-1-磷酸水平的影响与我们之前报道的相同：Li+浓度依赖性降低肌醇水平并增加肌醇-1-磷酸水平。因此，当以与7LiCl相同的剂量给药时，6LiCl对肌醇代谢产生更大的影响。当将6LiCl和7LiCl的剂量分别调整为5 mEq/kg和7 mEq/kg时，每组动物的皮层锂、肌醇和肌醇-1-磷酸水平大致相等，这表明同位素效应发生在组织摄取水平，而不是在肌醇磷酸代谢水平。两种锂同位素在体外对肌醇-1-磷酸酶的抑制作用没有差异。锂同位素对大脑皮层锂摄取的同位素效应与其他人报道的红细胞以及脑脊液/血浆比值的效应方向相同，但幅度更大。
