Regulation of mitochondrial contact sites in neonatal, juvenile and diabetic hearts.

摘要: Mitochondrial contact sites (MiCS) are dynamic structures involved in high capacity transport of energy from mitochondria into the cytosole. Previous studies revealed that normal conditions actual number MiCS is correlation with requirements heart, particularly those for its contractile work. Although detailed mechanisms signalling between processes utilisation and formation heart not yet elucidated, it known intracellular Ca2+ transients intimately this crosstalk. The present study devoted to investigation Ca2+-linked healthy adult hearts modified Ca2+-handling such as developing, juvenile diabetic myocardium. Experiments were performed on rats 22nd embryonal day, 1st, 4th, 7th 14th postnatal days well hearts. Diabetic investigated 8th day after streptozotocin injection (45 mg.kg–1i.v.) rats. Intracellular movements affected by modulation concentration perfusion solution (1.6 or 2.2 mmol.l–1) isolated, Langendorff-perfused hearts, calcium paradox (CaP) replacing Cd2+ ions. Elevation extracellular was reflected 30.1, 10.4 24.1% increase free adult, 14-day old respectively. In developing amount culminating 4th day. elevated solution, CaP diabetes led a significant amounts formed (58.1, 77.2 86.5% respectively; p 0.05). A replacement ions lowered (61 52.2%; < conclusion, during development, may be influenced both, permanent stimulation Ca2+-signalling availability mCPK. modulated response changes concentration. naturally attenuated, apparently consequence persisting alterations Ca2+-handling.