Ugur M, Turan B
Department of Biophysics, Faculty of Medicine, Ankara University, Sihhiye, Turkey.
Biol Trace Elem Res. 2001 Mar;79(3):235-45. doi: 10.1385/BTER:79:3:235.
Selenium is known to play an important role in the physiology of many different cell types and extracellular application of selenite causes cellular dysfunction in many different types of tissues. In a previous study, we have shown that in rat ventricles, sodium selenite (> or = 1 mM) caused an increase in the resting tension and a decrease in contractile force, in a time-dependent manner. In the present study, we have shown that sodium selenite caused a contracture state both in Langendorff perfused hearts and isolated papillary muscles. We also showed that the application of extracellular ATP (0.1 mM) markedly reduced this detrimental effect of sodium selenite on ventricular contraction in Langendorff perfused hearts and delayed it in isolated papillary muscle preparations. In contrast, isoproterenol (0.1 microM) did not seem to influence this action of sodium selenite in papillary muscle preparations. Possible reasons for this protective effect of ATP to selenite-induced contracture are also discussed.
已知硒在许多不同细胞类型的生理过程中发挥重要作用，亚硒酸盐的细胞外应用会导致许多不同类型组织中的细胞功能障碍。在先前的一项研究中，我们已经表明，在大鼠心室中，亚硒酸钠（≥1 mM）会导致静息张力增加和收缩力降低，且呈时间依赖性。在本研究中，我们已经表明，亚硒酸钠在Langendorff灌注心脏和分离的乳头肌中均会引起挛缩状态。我们还表明，细胞外ATP（0.1 mM）的应用显著降低了亚硒酸钠对Langendorff灌注心脏心室收缩的这种有害作用，并在分离的乳头肌制剂中延迟了这种作用。相比之下，异丙肾上腺素（0.1 microM）似乎对乳头肌制剂中亚硒酸钠的这种作用没有影响。还讨论了ATP对亚硒酸盐诱导的挛缩具有保护作用的可能原因。
