Pak Y, Huang L C, Lilley K J, Larner J
Department of Pharmacology, School of Medicine, University of Virginia, Charlottesville 22908.
J Biol Chem. 1992 Aug 25;267(24):16904-10.
We report here the in vivo conversion of [3H]myoinositol to [3H]chiroinositol. After labeling intraperitoneally with [3H]myoinositol for 3 days to reach radioisotope equilibrium in urine, [3H]chiroinositol was isolated from tissues and purified after 6 N HCl hydrolysis by two sequential paper chromatographies and high performance liquid chromatography (HPLC). Percent conversion of [3H]myoinositol to [3H]chiroinositol was highest in urine (36%), liver (8.8%), muscle (8.8%), and blood (7.6%) with intestine, brain, kidney, spleen, and heart decreasing in percentage from 2.8 to 0.7%. Labeling of other inositol isomers including scyllo-, neo-, and epi-, and mucoinositol was minimal, approximately 0.06% of [3H]myoinositol. Glucose was unlabeled, but glucuronate, the product of myoinositol oxidation, was labeled up to 1.5% of the [3H] myoinositol. Acid hydrolysates of combined inositol-containing phospholipids contain significant labeled chiroinositol. [3H]Phosphatidylinositols and [3H]glycosylphosphatidylinositols were extracted from liver, muscle, and blood, isolated by thin layer chromatography, and inositols purified by HPLC after acid hydrolysis. Percent conversion of [3H]myoinositol to [3H] chiroinositol was highest in blood (60.4%) followed by muscle (7.7%) and liver (2.2%).
我们在此报告了[3H]肌醇在体内向[3H]手性肌醇的转化。用[3H]肌醇腹膜内标记3天以使尿液中的放射性同位素达到平衡后，从组织中分离出[3H]手性肌醇，并在6N盐酸水解后通过两次连续的纸色谱法和高效液相色谱法（HPLC）进行纯化。[3H]肌醇向[3H]手性肌醇的转化率在尿液中最高（36%），其次是肝脏（8.8%）、肌肉（8.8%）和血液（7.6%），而肠道、大脑、肾脏、脾脏和心脏的转化率则从2.8%降至0.7%。包括半缩醛肌醇、新肌醇、表肌醇和粘液肌醇在内的其他肌醇异构体的标记极少，约为[3H]肌醇的0.06%。葡萄糖未被标记，但肌醇氧化产物葡萄糖醛酸的标记量高达[3H]肌醇的1.5%。含肌醇磷脂混合物的酸水解产物含有大量标记的手性肌醇。从肝脏、肌肉和血液中提取[3H]磷脂酰肌醇和[3H]糖基磷脂酰肌醇，通过薄层色谱法分离，并在酸水解后通过HPLC纯化肌醇。[3H]肌醇向[3H]手性肌醇的转化率在血液中最高（60.4%），其次是肌肉（7.7%）和肝脏（2.2%）。
