[Antihypoxic effects of quinones connected with restoration of electro-transport and function of the respiratory chain of the isolated rat heart].

The effect of hypoxia of middle severity (H50) has been investigated on the contractile activity, oxidative metabolism and bioenergetic function of the myocardium in the isolated rat heart. It has been shown that differences in the functional-metabolic parameters sensitivity in the resistant and non-resistant to hypoxia animals are defined by the primary utilization of different pathways of substrates oxidation--the succinate-oxidative pathway of oxidation or the NADH-oxidative pathway, correspondingly. It is possible to correct the early hypoxic injuries of the electron-transfer function of the myocardium respiratory chain at the NADH-CoQ region (the first enzyme complex) with the help of quinones (vitamin K3, hydroquinone). The mechanism of this correction depends on the donor-acceptor properties of these compounds and it is the same both in the myocardium of the isolated heart and in the isolated mitochondria. Vitamin K3 is recommended to be utilized on the early stages of hypoxic injuries in myocardium as an antihypoxant of the energized type.