Bakhle Y S, Moncada S, de Nucci G, Salmon J A
Br J Pharmacol. 1985 Sep;86(1):55-62. doi: 10.1111/j.1476-5381.1985.tb09434.x.
The effects of infusions of bradykinin (0.2 microM), calcium ionophore A23187 (0.5 microM) and arachidonic acid (13 microM) on the release of eicosanoids from the guinea-pig isolated perfused lung were investigated using radioimmunoassay for thromboxane B2 (TXB2), 6-oxo-prostaglandin F1 alpha (6-oxo-PGF1 alpha), PGE2, leukotriene B4 (LTB4) and LTC4 and bioassay using the superfusion cascade. Bradykinin released more 6-oxo-PGF1 alpha than TXB2, whereas arachidonic acid and ionophore released more TXB2 than 6-oxo-PGF1 alpha. The time course of eicosanoid release varied with the stimulus: bradykinin and arachidonic acid produced an immediate release, whereas the ionophore showed a slower onset of release. Although the amounts of LTB4 and LTC4 released by the ionophore were very low according to radioimmunoassays, there was evidence from the bioassay of release of a leukotriene-like substance, thought to be LTD4. The leukotriene antagonist FPL 55712 lacks specificity in the guinea-pig trachea; at the concentration used (2 microM) it antagonized contractions of the tracheal strip to PGE2 as well as to LTC4. Our results show that in the guinea-pig perfused lung the metabolism of exogenous arachidonic acid is both qualitatively and quantitatively different from the metabolism of endogenous arachidonic acid; furthermore, the profile of eicosanoid production is stimulus-dependent.
利用放射免疫分析法检测血栓素B2（TXB2）、6-氧代前列腺素F1α（6-氧代-PGF1α）、前列腺素E2（PGE2）、白三烯B4（LTB4）和白三烯C4（LTC4），并采用灌注级联生物分析法，研究了缓激肽（0.2微摩尔）、钙离子载体A23187（0.5微摩尔）和花生四烯酸（13微摩尔）对豚鼠离体灌注肺中类花生酸释放的影响。缓激肽释放的6-氧代-PGF1α比TXB2多，而花生四烯酸和离子载体释放的TXB2比6-氧代-PGF1α多。类花生酸释放的时间进程因刺激因素而异：缓激肽和花生四烯酸引起立即释放，而离子载体的释放起始较慢。尽管根据放射免疫分析，离子载体释放的LTB4和LTC4量非常低，但生物分析有证据表明释放了一种白三烯样物质，认为是白三烯D4（LTD4）。白三烯拮抗剂FPL 55712在豚鼠气管中缺乏特异性；在所用浓度（2微摩尔）下，它能拮抗气管条对PGE2以及LTC4的收缩反应。我们的结果表明，在豚鼠灌注肺中，外源性花生四烯酸的代谢在质和量上均不同于内源性花生四烯酸的代谢；此外，类花生酸产生的谱型依赖于刺激因素。
