Lasnier E, Blanc M C, Housset C, Rey C, Roch-Arveiller M, Vaubourdolle M
Service de Biochimie A, INSERM U 402, Hôpital Saint-Antoine, AP-HP, Paris, Service de Biochimie A, Hôtel Dieu, AP-HP, Paris, CNRS URA 1534, Hôpital Cochin, Paris, France.
Liver. 2002 Dec;22(6):495-500. doi: 10.1034/j.1600-0676.2002.01668.x.
Interactions between polymorphonuclear leukocytes (PMN) and sinusoidal endothelial cells (SEC) may contribute to ischemia-reperfusion injury. The aim of the study was to determine the influence of PMN hypoxia-reoxygenation and degranulation, on SEC toxic response.
PMNs collected from rat pleural cavity underwent hypoxia- reoxygenation or N-formyl-methionyl-leucyl-phenylalanine (fMLP) degranulation treatment, and were then separated from their conditioned medium. Rat SECs were incubated either with PMNs in coculture or with their conditioned medium, for 210 min. Oxidative metabolism in PMNs was measured by chemiluminescence. LDH release and elastase activity were measured in SEC supernatants.
PMN-conditioned medium induced an increase in LDH release in SECs. Hypoxia-reoxygenation of PMNs induced an increase in their chemiluminescent response without increasing the cytotoxic effect of their conditioned medium. By contrast, the cytotoxic effect of conditioned medium was increased following PMN treatment with fMLP. In the latter case, cytotoxicity was combined with a rise in the elastase activity released in the supernatants, but was not reduced by inhibitors of elastase or of other proteases.
The results indicate that toxic products are released, at least in part through degranulation, by PMNs, and induce cytotoxicity in SECs. This mechanism may contribute to SEC injury during hypoxia-reoxygenation.
多形核白细胞（PMN）与肝血窦内皮细胞（SEC）之间的相互作用可能导致缺血再灌注损伤。本研究旨在确定PMN缺氧复氧和脱颗粒对SEC毒性反应的影响。
从大鼠胸腔收集的PMN进行缺氧复氧或N-甲酰甲硫氨酰亮氨酰苯丙氨酸（fMLP）脱颗粒处理，然后将其与条件培养基分离。将大鼠SEC与共培养的PMN或其条件培养基孵育210分钟。通过化学发光法测量PMN中的氧化代谢。测量SEC上清液中的乳酸脱氢酶（LDH）释放和弹性蛋白酶活性。
PMN条件培养基诱导SEC中LDH释放增加。PMN的缺氧复氧诱导其化学发光反应增加，而不增加其条件培养基的细胞毒性作用。相比之下，用fMLP处理PMN后，条件培养基的细胞毒性作用增强。在后一种情况下，细胞毒性与上清液中释放的弹性蛋白酶活性升高相关，但不受弹性蛋白酶或其他蛋白酶抑制剂的影响。
结果表明，PMN至少部分通过脱颗粒释放毒性产物，并在SEC中诱导细胞毒性。这种机制可能导致缺氧复氧期间SEC损伤。
