Danylovych Iu V, Kolomiiets' O V, Danylovych H V, Kosterin S O
Fiziol Zh (1994). 2014;60(2):12-7.
The influence of the donor and the precursor of NO, namely 100 mM sodium nitroprusside and sodium nitrite on the energo-dependent Ca(2+)-transport in isolated mitochondria from rat myometrium was investigated. Changes in the mitochondrial matrix Ca(2+)-concentration was evaluated by spectrofluorimetry using Ca2+ sensitive probe Fluo-4 AM. Mg(2+)-ATP-dependent Ca(2+)-accumulation on mitochondria in the presence of succinate significantly stimulated by nitric oxide, in particular, 100 microM sodium nitroprusside amplified the transport by 1.6 times relative to its control values. NO effect becomes significant only when the incubation of mitochondria with the compounds was performed. Ca(2+)-accumulation in the presence of sodium nitroprusside effectively suppressed by protonophore (CCCP) and ruthenium red (10 microM). It was concluded that inner mitochondrial membrane Ca(2+)-uniporter stimulated by nitrogen oxide. Ca(2+)-accumulation in mitochondria in the presence of sodium nitroprusside was not sensitive to the action of a specific permeability transition pore inhibitor cyclosporine (5 microM). This data indicates that the role of permeability transition pore is less significant than Ca(2+)-uniporter in the processes of Ca(2+)-transport in mitochondria under the nitric oxide action. Thus, nitric oxide stimulates the energo-dependent Ca(2+)-accumulation by myometrium mitochondria mediated their inner membrane Ca(2+)-uniporter functioning.
研究了一氧化氮（NO）的供体及前体，即100 mM硝普钠和亚硝酸钠对大鼠子宫肌层分离线粒体中能量依赖性Ca(2+)转运的影响。使用Ca2+敏感探针Fluo-4 AM通过荧光分光光度法评估线粒体基质中Ca(2+)浓度的变化。在琥珀酸存在下，一氧化氮显著刺激了Mg(2+)-ATP依赖性Ca(2+)在线粒体上的积累，特别是100 microM硝普钠使转运相对于其对照值增加了1.6倍。只有当线粒体与这些化合物一起孵育时，NO的作用才变得显著。质子载体（CCCP）和钌红（10 microM）有效地抑制了硝普钠存在下的Ca(2+)积累。得出的结论是，线粒体内膜Ca(2+)单向转运体受氮氧化物刺激。硝普钠存在下线粒体中的Ca(2+)积累对特异性通透性转换孔抑制剂环孢素（5 microM）的作用不敏感。该数据表明，在一氧化氮作用下，通透性转换孔在Ca(2+)在线粒体中转运过程中的作用不如Ca(2+)单向转运体重要。因此，一氧化氮通过子宫肌层线粒体介导其内膜Ca(2+)单向转运体的功能，刺激了能量依赖性Ca(2+)的积累。
