ALBUMIN STIMULATES THE RELEASE OF LYSOPHOSPHATIDYLCHOLINE FROM CULTURED RAT HEPATOCYTES
ALBUMIN STIMULATES THE RELEASE OF LYSOPHOSPHATIDYLCHOLINE FROM CULTURED RAT HEPATOCYTES
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DOI：
10.1042/bj2530693
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发表时间：
1988-08-01
影响因子：
4.1
通讯作者：
VANCE, DE
中科院分区：
文献类型：
--
作者：
BAISTED, DJ;ROBINSON, BS;VANCE, DE
本文研究了白蛋白对[Me-3 H]胆碱预标记培养大鼠肝细胞释放[3 H]溶血磷脂酰胆碱的影响。在培养基中不含血清和白蛋白的情况下，细胞基本上不释放[3 H]溶血磷脂酰胆碱。白蛋白显著地刺激该过程，并且在2 mg/ml时达到平台。[3 H]溶血磷脂酰胆碱的释放在30 min的初始滞后后至少4 h呈线性。在低浓度下，白蛋白轻微刺激[3 H]磷脂酰胆碱释放。白蛋白对细胞[3 H]磷脂酰胆碱、[3 H]溶血磷脂酰胆碱或[3 H]甘油磷酸胆碱的代谢无可测量的影响。此外，白蛋白并没有改变释放的3 H-标记的水溶性化合物，包括[3 H]甘油磷酸胆碱，到介质中。排除了[3 H]溶血磷脂酰胆碱是由分泌酶催化培养基中的[3 H]磷脂酰胆碱产生的可能性。当细胞与α-H2O孵育时，也观察到对[3 H]溶血磷脂酰胆碱分泌的影响。环糊精是一种能够结合溶血磷脂酰胆碱的环状多糖。白蛋白释放的溶血磷脂酰胆碱富含不饱和脂肪酸。培养液中细胞磷脂酰胆碱脂肪酸组成的变化。它的结论是，磷脂酰胆碱不断被降解的大鼠肝细胞溶血磷脂酰胆碱释放到介质中，只有当一个合适的受体存在。
The effect of albumin on the release of [3H]lysophosphatidylcholine from cultured rat hepatocytes prelabelled with [Me-3H]choline was studied. In the absence of serum and albumin from the medium, the cells released essentially no [3H]lysophosphatidylcholine. Albumin stimulated this process dramatically, and it reached a plateau at 2 mg/ml. After an initial lag of 30 min, the release of [3H]lysophosphatidylcholine was linear for at least 4 h. At low concentrations, albumin slightly stimulated [3H]phosphatidylcholine release. The albumin had no measurable effect on the metabolism of cellular [3H]phosphatidylcholine, [3H]lysophosphatidylcholine or [3H]glycerophosphocholine. In addition, albumin did not alter the release of 3H-labelled water-soluble compounds, including [3H]glycerophosphocholine, into the medium. The possibility that the [3H]lysophosphatidylcholine was arising from catabolism of [3H]phosphatidylcholine in the medium by secreted enzymes was excluded. The effect on [3H]lysophosphatidylcholine secretion was also observed when the cells were incubated with .alpha.-cyclodextrin, a cyclic polysaccharide that has the ability to bind lysophosphatidylcholine. The albumin-released lysophosphatidylcholine was enriched in unsaturated fatty acids. Alteration of the fatty acid composition of cellular phosphatidylcholine in the medium. It is concluded that phosphatidylcholine is constantly being degraded in the rat hepatocyte to lysophosphatidylcholine which is released into the medium only when a suitable acceptor is present.