Lekka M E, Tsoukatos D, Kapoulas V M
Department of Chemistry, University of Ioannina, Greece.
Biochim Biophys Acta. 1990 Feb 6;1042(2):217-20. doi: 10.1016/0005-2760(90)90011-l.
The metabolism of exogenous platelet-activating-factor was studied in the protozoan Tetrahymena pyriformis in vivo. When the cells are exposed to 1.10(-6) M PAF, the molecule is rapidly metabolized to 1-O-alkyl-2-acyl(long chain)-GPC, a major component of the protozoan membranes. The appearance of lyso-PAF from the first minutes even in low levels provides evidence that deacetylation is an intermediate step. After incubation for 30 min, transformation to aminoethyl phosphonolipids is also observed. The fate of PAF in concentrations 1.5.10(-11) M or 1.10(-8) M PAF, was the same. An amount of PAF depending on the external PAF concentration remained intact in the cell even after 1 h incubation. Our results suggest that the easily cultured protozoan can be a useful model for studying PAF's metabolism.
研究了外源性血小板活化因子在梨形四膜虫体内的代谢情况。当细胞暴露于1.10（-6）M的血小板活化因子时，该分子会迅速代谢为1-O-烷基-2-酰基（长链）-甘油磷脂酰胆碱，这是原生动物膜的主要成分。即使在最初几分钟内溶血型血小板活化因子的含量很低，但其出现也证明脱乙酰化是一个中间步骤。孵育30分钟后，还观察到向氨乙基磷脂的转化。1.5.10（-11）M或1.10（-8）M血小板活化因子浓度下血小板活化因子的命运是相同的。即使孵育1小时后，细胞内仍有一定量取决于外部血小板活化因子浓度的血小板活化因子保持完整。我们的结果表明，这种易于培养的原生动物可以成为研究血小板活化因子代谢的有用模型。
