SYNTHESIS OF PHOSPHATIDYLCHOLINE IN GUINEA-PIG FETAL LUNG INVOLVES ACYL REMODELING AND DIFFERENTIAL TURNOVER OF INDIVIDUAL MOLECULAR-SPECIES
SYNTHESIS OF PHOSPHATIDYLCHOLINE IN GUINEA-PIG FETAL LUNG INVOLVES ACYL REMODELING AND DIFFERENTIAL TURNOVER OF INDIVIDUAL MOLECULAR-SPECIES
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DOI：
10.1016/0005-2760(93)90105-i
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发表时间：
1993-02-24
期刊：
影响因子：
--
通讯作者：
POSTLE, AD
中科院分区：
文献类型：
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作者：
BURDGE, GC;KELLY, FJ;POSTLE, AD
通过在子宫内将50 μ Ci [甲基-C-14]胆碱掺入肺PC中3小时，确定了发育中胎豚鼠肺表面活性物质合成期间（d）55天至足月（d 68）期间双饱和磷脂酰胆碱（PC）分子种类在发育中胎豚鼠肺中蓄积的机制。PC从头合成的模式与总PC池的组成的比较表明，约。总PC 16：0/16：0的50%是通过磷脂酶A2和酰基转移酶的作用对PC 16：0/18：2进行酰基重构而合成的。酰基重塑在表面活性剂合成开始之前（d55）建立，因此对该过程不是特异性的。从第55天到足月，肺PC浓度显着增加。相反，在此期间，[C-14]胆碱掺入肺组织和PC合成速率下降。肺PC物种的周转时间的计算表明，在表面活性剂的生产过程中，肺disaturated PC浓度的增加可能是由于catalysts，而不是增加PC合成的差异减少。
The mechanisms for accumulation of disaturated phosphatidylcholine (PC) molecular species in developing fetal guinea-pig lung during the period of surfactant synthesis, between day (d) 55 and term (d68), were determined by the incorporation of 50 muCi [methyl-C-14]choline into lung PC in utero over 3 h. Comparison of the pattern of PC synthesis de novo with the composition of the total PC pool indicated that approx. 50% of the total PC16:0/16:0 was synthesized by acyl remodelling of PC16:0/18:2 by the actions of phospholipase A2 and acyltransferases. Acyl remodelling was established before the onset of surfactant synthesis (d55) and so was not specific for this process. Between d55 and term the concentration of lung PC increased significantly. Conversely, the incorporation of [C-14]choline into lung tissue and the rate of PC synthesis decreased over this period. Calculation of turnover times of lung PC species suggested that the increase in lung disaturated PC concentration during surfactant production might be due to a differential decrease in catabolism rather than increased PC synthesis.