Toninello A, Di Lisa F, Siliprandi D, Siliprandi N
Biochim Biophys Acta. 1985 May 28;815(3):399-404. doi: 10.1016/0005-2736(85)90366-9.
Spermine, a polyamine present in the mammalian cells at rather high concentration, has, among other actions, a remarkable stabilizing effect on mitochondria, functions which have generally been attributed to the capability of this and other polyamines to bind to membrane anionic sites. In the present paper evidence is provided that at physiological concentrations spermine may also be transported into rat liver mitochondrial matrix space, provided that mitochondria are energized and inorganic phosphate is simultaneously transported. The close dependence of spermine transport is also demonstrated by the concurrent efflux of spermine and inorganic phosphate when mitochondria preloaded with the two ionic species are deenergized either with uncouplers or respiratory chain inhibitors. Furthermore, Mersalyl, the known inhibitor of phosphate transport, prevents both spermine uptake and release. Mg2+ inhibits the transport of spermine conceivably by competing for the some binding sites on the mitochondrial membrane. The physiological significance of these results is discussed.
精胺是一种在哺乳动物细胞中以相当高浓度存在的多胺，除其他作用外，它对线粒体具有显著的稳定作用，这些功能通常归因于这种多胺和其他多胺与膜阴离子位点结合的能力。本文提供的证据表明，在生理浓度下，只要线粒体处于活跃状态且无机磷酸盐同时被转运，精胺也可能被转运到大鼠肝脏线粒体基质空间。当预先加载了这两种离子的线粒体用解偶联剂或呼吸链抑制剂使其失去能量时，精胺和无机磷酸盐同时外流，这也证明了精胺转运的紧密依赖性。此外，已知的磷酸盐转运抑制剂汞撒利可同时阻止精胺的摄取和释放。Mg2+可能通过竞争线粒体膜上的某些结合位点来抑制精胺的转运。本文讨论了这些结果的生理学意义。
