Mayer A M, Spitzer J A
Department of Physiology, Louisiana State University Medical Center, New Orleans 70122-1393.
Infect Immun. 1991 Dec;59(12):4590-8. doi: 10.1128/iai.59.12.4590-4598.1991.
Continuous infusion of a nonlethal dose of Escherichia coli lipopolysaccharide (LPS) (0.5 mg/kg) induced early (3 h) accumulation of polymorphonuclear leukocytes (PMNL) in rat liver followed by later (30 h) greater extravasation of mononuclear phagocytes (MNP) (E. B. Rodriguez de Turco and J. A. Spitzer, J. Leukocyte Biol. 48:488-494, 1990). Nonparenchymal liver cells from rats treated for 3 and 30 h with LPS were recovered by centrifugal elutriation, yielding a 23-ml/min fraction (endothelial cells) and a 45-ml/min fraction (PMNL, Kupffer cells, and MNP), and compared for their capacity for basal and agonist-stimulated superoxide (O2-) production. Stimulation with phorbol myristate acetate and opsonized zymosan caused a dose-dependent release of O2- from the 45-ml/min fraction derived from rats treated for 3 h with saline, but not from the 23-ml/min fraction. Further purification of the 45-ml/min fraction by discontinuous density gradient centrifugation into a Kupffer and a PMNL fraction revealed that most of the agonist-induced O2- release was generated by infiltrating PMNL at this early time point of LPS infusion. By 30 h of LPS infusion, although enhancement of the phorbol-12-myristate-13-acetate- and opsonized zymosan-stimulated release of O2- was observed in the 45-ml/min fraction, but not in the 23-ml/min fraction, the maximum release of O2- was smaller than that observed in the rats treated for 3 h. Our results support the following conclusions: (i) after a 3-h LPS infusion, PMNL found in the liver in increased numbers are also highly primed for agonist-stimulated release of O2-, while Kupffer cell priming is of a lesser extent; (ii) after a 30-h infusion of LPS, infiltrating MNP found in the liver in increased numbers are primed for agonist-induced O2- release, while priming of PMNL has diminished; (iii) at both 3 and 30 h of LPS infusion, liver endothelial cells are not significantly primed for agonist-stimulated O2- release; and (iv) in vivo priming by LPS infusion at both 3 and 30 h was not reversed by the experimental method used for cell recovery (ca. 3 h), thus suggesting that in vivo LPS priming of O2- release may ultimately lead to severe impairment of liver function and metabolism observed during endotoxemia and sepsis if not therapeutically blocked at an early time point.
持续输注非致死剂量的大肠杆菌脂多糖（LPS）（0.5毫克/千克）会导致大鼠肝脏中多形核白细胞（PMNL）在早期（3小时）积聚，随后在后期（30小时）单核吞噬细胞（MNP）出现更大程度的渗出（E.B.罗德里格斯·德·图尔科和J.A.斯皮策，《白细胞生物学杂志》48:488 - 494，1990）。通过离心淘洗回收经LPS处理3小时和30小时的大鼠非实质肝细胞，得到一个23毫升/分钟的组分（内皮细胞）和一个45毫升/分钟的组分（PMNL、库普弗细胞和MNP），并比较它们基础和激动剂刺激的超氧化物（O₂⁻）产生能力。用佛波酯肉豆蔻酸酯乙酸盐和调理酵母聚糖刺激导致从用生理盐水处理3小时的大鼠获得的45毫升/分钟组分中剂量依赖性地释放O₂⁻，但23毫升/分钟组分中未出现这种情况。通过不连续密度梯度离心将45毫升/分钟组分进一步纯化成分离的库普弗细胞组分和PMNL组分，结果显示在LPS输注的这个早期时间点，大部分激动剂诱导的O₂⁻释放是由浸润的PMNL产生的。到LPS输注30小时时，尽管在45毫升/分钟组分中观察到佛波醇-12-肉豆蔻酸酯-13-乙酸盐和调理酵母聚糖刺激的O₂⁻释放增强，而23毫升/分钟组分中未观察到，但O₂⁻的最大释放量小于在处理3小时的大鼠中观察到的量。我们的结果支持以下结论：（i）LPS输注3小时后，肝脏中数量增加的PMNL对激动剂刺激的O₂⁻释放也高度敏感，而库普弗细胞的敏感性较低；（ii）LPS输注30小时后，肝脏中数量增加的浸润MNP对激动剂诱导的O₂⁻释放敏感，而PMNL的敏感性已降低；（iii）在LPS输注3小时和30小时时，肝脏内皮细胞对激动剂刺激的O₂⁻释放均未显著敏感；（iv）在3小时和30小时通过LPS输注进行的体内致敏不会因用于细胞回收的实验方法（约3小时）而逆转，因此表明如果在内毒素血症和脓毒症期间未在早期时间点进行治疗性阻断，LPS体内对O₂⁻释放的致敏最终可能导致严重的肝功能和代谢损害。
