BIOSYNTHESIS OF PHOSPHATIDYLCHOLINES IN RAT LIVER
BIOSYNTHESIS OF PHOSPHATIDYLCHOLINES IN RAT LIVER
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DOI：
10.1111/j.1432-1033.1968.tb00385.x
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发表时间：
1968-01-01
期刊：
影响因子：
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通讯作者：
ARVIDSON, GA
中科院分区：
文献类型：
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作者：
ARVIDSON, GA
本文研究了L-[Me-14C]蛋氨酸的[1，2-14C2]胆碱和甲基在大鼠肝脏和血浆磷脂酰胆碱亚组分中的掺入。在硝酸银浸渍的平板上用薄层层析分离，然后用反相分配薄层层析分离得到8种不同分子类型的磷脂酰胆碱。在肝脏中，[1，2-14C2]胆碱在棕榈酰-油酰基和棕榈酰亚油酰磷脂酰胆碱中的掺入最快，而在硬脂酰基-花生四烯基胆碱中很慢。最初，注射[1，2-14C2]胆碱后，血浆中不同不饱和程度的磷脂酰胆碱的亚组分中的同位素分布与肝脏中的磷脂酰胆碱的分布非常相似。大约80%的被结合的同位素存在于单烯和双烯馏分中。注射L-[Me-14C]蛋氨酸后，肝组织中的四烯和六烯类磷脂酰胆碱占总磷脂酰胆碱的75%~85%。这些血浆组分中的同位素比例较低。在肝脏中的多不饱和磷脂酰胆碱中，那些含有棕榈酸和二十二碳六烯酸的磷脂酰胆碱与L-[Me-14C]蛋氨酸的同位素结合程度高于所有类型磷脂酰乙醇胺化学计量甲基化的预期程度。硬脂酰亚组分表现出最低的代谢反应活性。在雄性和雌性大鼠中，在禁食期间，每只大鼠整个肝脏中单烯和双烯组分的数量都大大减少。
The incorporation of [1,2‐14C2]choline and methyl groups from L‐[Me‐14C]methionine into subfractions of phosphatidylcholines of liver and blood plasma in the rat has been studied. Fractionation by thin‐layer chromatography on AgNO3‐impregnated plates followed by reversedphase partition thin‐layer chromatography permitted the isolation of 8 different molecular types of phosphatidylcholines. In the liver, incorporation of [1,2‐14C2]choline occurred most rapidly in palmitoyl‐oleoyl and palmitoyl‐linoleoyl phosphatidylcholine but was very slow in the stearoyl‐arachidonoyl species. Initially, after injection of [1,2‐14C2]choline, the distribution of isotope in the subfractions of different degree of unsaturation of the phosphatidylcholines in blood plasma was very similar to that of the phosphatidylcholines in the liver. Approximately 80% of the incorporated isotope was found in the mono‐ and dienoic fractions. After administration of L‐[Me‐14C]methionine the tetra and hexaenoic liver phosphatidylcholines contained 75 to 85% of the total [14C]phosphatidylcholine. The proportion of isotope in these fractions of blood plasma was lower. Among the polyunsaturated phosphatidylcholines in liver those containing palmitic and docosahexaenoic acid were found to incorporate isotope from L‐[Me‐14C]methionine to a greater extent than would be expected from a stoichiometric methylation of all types of phosphatidylethanolamines. The stearoyl‐arachidonoyl subfraction exhibited the lowest metabolic reactivity. In both male and female rats the amounts per whole liver of the mono‐ and dienoic fractions were greatly reduced during fasting.