Nayler W G, Grinwald P M
Am J Physiol. 1982 Feb;242(2):H203-10. doi: 10.1152/ajpheart.1982.242.2.H203.
Experiments were undertaken to establish whether Ba2+ can substitute for Ca2+ in maintaining the structural and functional integrity of the glycocalyx. Adult rat hearts were perfused with Ca2+-free buffer at 37 degrees C, with and without added Ba2+. Ten minutes later Ba2+-free, Ca-containing medium was reintroduced. Hearts that had been perfused with Ca2+-free medium exhibited a distorted glycocalyx. On reperfusion with Ca2+-containing medium these hearts released protein (P less than 0.001), gained Ca2+ (P less than 0.001), and depleted their tissue stores of ATP (P less than 0.001) and CP (P less than 0.001). Hearts that had been perfused with Ca2+-free, Ba2+-containing medium retained an apparently intact glycocalyx. On reperfusion with Ca2+-containing. Ba2+-free medium they gained Ca2+ but did not lose protein. These results suggest that Ba2+ only partially replaces Ca2+ in maintaining the integrity of the cell surface. It is also concluded that the absence of protein release does not necessarily exclude the occurrence of severe changes in ionic permeability after cell injury.
开展实验以确定Ba2+在维持糖萼的结构和功能完整性方面是否能够替代Ca2+。成年大鼠心脏在37℃下用不含Ca2+的缓冲液灌注，添加或不添加Ba2+。10分钟后，重新引入不含Ba2+、含Ca2+的培养基。用不含Ca2+的培养基灌注的心脏表现出糖萼扭曲。在用含Ca2+的培养基再灌注时，这些心脏释放蛋白质（P<0.001），摄取Ca2+（P<0.001），并耗尽其组织中的ATP（P<0.001）和CP（P<0.001）。用不含Ca2+、含Ba2+的培养基灌注的心脏保留了明显完整的糖萼。在用含Ca2+、不含Ba2+的培养基再灌注时，它们摄取Ca2+但不丢失蛋白质。这些结果表明，Ba2+在维持细胞表面完整性方面仅部分替代Ca2+。还得出结论，蛋白质未释放并不一定排除细胞损伤后离子通透性发生严重变化的情况。
