Akopova O V, Sagach V F
Ukr Biokhim Zh (1999). 2004 Sep-Oct;76(5):61-5.
It is shown that mitochondria of rat myocardium exhibit high sensitivity to Ca2+-induced permeability transition pore (PTP) during an hour after their isolation. The threshold Ca2+ concentrations necessary to induce PTP are as low as 25-50 nmol/mg of protein. Apparent K(Ca) constant of Ca2+-dependent PTP activation is 40 microM. Incubation of mitochondria during 2, 3 and 4 hours after their isolation leads to gradual increase in K(Ca) values up to 0.4 microM, which is accompanied by simultaneous decrease in sensitivity of mitochondria to pore opening. A correlation is supposed between changes of kinetic parameters of Ca2+-uniporter and changes in sensitivity of mitochondria to Ca2+-induced permeability transition.
结果表明，大鼠心肌线粒体在分离后的一小时内对钙离子诱导的通透性转换孔（PTP）表现出高敏感性。诱导PTP所需的阈值钙离子浓度低至25 - 50 nmol/mg蛋白质。钙离子依赖性PTP激活的表观K（Ca）常数为40 microM。线粒体在分离后2、3和4小时的孵育导致K（Ca）值逐渐增加至0.4 microM，同时伴随着线粒体对孔开放的敏感性降低。推测钙离子单向转运体的动力学参数变化与线粒体对钙离子诱导的通透性转换的敏感性变化之间存在相关性。
