Brierley G P
Mol Cell Biochem. 1976 Jan 31;10(1):41-63. doi: 10.1007/BF01731680.
The factors involved in the movement of monovalent cations across the inner membrane of the isolate heart mitochondrion are reviewed. The evidence suggests that the energy-dependent uptake of K+ and Na+ which results in swelling of the matrix is an electrophoretic response to a negative internal potential. There are no clear cut indications that this electrophoretic cation movement is carrier-mediated and possible modes of entry which do not require a carrier are examined. The evidence also suggests that the monovalent cation for proton exchanger (Na+ greater than K+) present in the membrane may participate in the energy-dependent extrusion of accumulated ions. The two processes, electrophoreti c cation uptake (swelling) and exchange-dependent cation extrusion (contraction) may represent a means of controlling the volume of the mitochondrion within the functioning cell. A number of indications point to the possibility that the volume control process may be mediated by the divalent cations Ca+2 and Mg+2. Studies with mercurial reagents also implicate certain membrane thiol groups in the postulated volume control process.
本文综述了单价阳离子跨离体心脏线粒体内膜转运所涉及的因素。证据表明，导致基质肿胀的钾离子和钠离子的能量依赖性摄取是对负内部电位的一种电泳反应。目前尚无明确迹象表明这种电泳阳离子转运是由载体介导的，本文研究了不需要载体的可能进入方式。证据还表明，膜中存在的单价阳离子-质子交换体（钠离子大于钾离子）可能参与了积累离子的能量依赖性排出。这两个过程，即电泳阳离子摄取（肿胀）和交换依赖性阳离子排出（收缩），可能是控制功能细胞内线粒体体积的一种方式。许多迹象表明，体积控制过程可能由二价阳离子钙离子和镁离子介导。用汞试剂进行的研究也表明，某些膜硫醇基团参与了假定的体积控制过程。
