Dynamic Restructuring of the Myocardial Mitochondria in Response to Uridine Modulation of the Activity of Mitochondrial ATP-Dependent Potassium Channel under Conditions of Acute Hypoxic Hypoxia.

We studied the effects of in vivo modulation of activity of mitochondrial ATP-dependent potassium channel (mitoKATP) by uridine on the morphofunctional state of mitochondria in rat cardiomyocytes under conditions of acute hypoxia. Preinjection of uridine to animals reduced the number of structurally modified mitochondria, but had practically no effect on their morphogenesis after hypoxia. Uridine in vivo stimulated the formation of micromitochondria and their release into the cytoplasm. The number of "maternal" mitochondria containing three and more new micromitochondria, increased as well. The use of mitoKATP blocker 5-hydroxydecanoate in parallel with uridine abolished its protective effect, as it significantly inhibited the formation of micromitochondria in rat cardiomyocytes after acute hypoxic exposure.