Amirkhanian J D, Taeusch H W
Department of Pediatrics, Drew University, Los Angeles, CA.
Biochim Biophys Acta. 1993 Jan 10;1165(3):321-6. doi: 10.1016/0005-2760(93)90143-w.
Several mechanisms for surfactant inactivation have been reported. In this study, we have measured the reversibility of surfactant inactivation caused by various lipid or protein constituents of plasma or by pH changes. A surfactant of bovine origin was studied in a pulsating surfactometer either when surfactants were premixed with different serum constituents (inactivators) or when inactivators were introduced into subphase fluid surrounding surfactant films formed at an air-liquid interface. Subphase exchanges with sodium bicarbonate or sodium borate raised pH and raised minimal surface tensions either when premixed with surfactant or when introduced with saline subphase beneath a preformed surfactant surface film. The pH effects on surfactant film function were reversible for sodium bicarbonate but not for sodium borate when the subphase with bicarbonate or borate was replaced with saline. Lipids (platelet-activating factor or lysophosphatidylcholine) had non-reversible effects on preformed films. Proteins (fibrinogen or C reactive protein) had reversible effects at low concentrations, but reversibility was less evident at high concentrations. Effects with whole serum were non-reversible at low protein concentrations (0.5 mg/ml). These results add evidence that surfactant inactivation can be caused by multiple mechanisms, both reversible and irreversible.
已有多种表面活性剂失活机制的报道。在本研究中，我们测定了由血浆的各种脂质或蛋白质成分或pH变化引起的表面活性剂失活的可逆性。在脉动表面张力仪中研究了牛源性表面活性剂，一种情况是将表面活性剂与不同血清成分（失活剂）预混合，另一种情况是将失活剂引入气液界面形成的表面活性剂膜周围的亚相流体中。用碳酸氢钠或硼酸钠进行亚相交换会提高pH值，并提高最小表面张力，无论是在与表面活性剂预混合时，还是在预先形成的表面活性剂表面膜下方用盐水亚相引入时。当用盐水替代含碳酸氢盐或硼酸盐的亚相时，碳酸氢钠对表面活性剂膜功能的pH效应是可逆的，而硼酸钠则不可逆。脂质（血小板活化因子或溶血磷脂酰胆碱）对预先形成的膜有不可逆作用。蛋白质（纤维蛋白原或C反应蛋白）在低浓度时有可逆作用，但在高浓度时可逆性不太明显。在低蛋白浓度（0.5mg/ml）时，全血清的作用是不可逆的。这些结果进一步证明，表面活性剂失活可由多种机制引起，包括可逆和不可逆机制。
