[Brain bioenergetic parameters in rats with varying resistance to hypoxia]

Spontaneous electrical activity, adenyl nucleotides' and cytochromes' contents, activity of respiratory chain enzymes complex in brain slices, homogenate and isolated mitochondria of rats, preliminary divided into non-resistant (NR) and high resistant (HR) animals by their sensitivity to hypobaric hypoxia have been investigated. It has been shown that in HR animals brain slices high resistant to hypoxia neurons and in NR brain slices non-resistant neurons predominate. ATP content and energetic charge in the HR animals brain slice were maintained at more high level than in NR. The reduction of NAD-depended way of oxidation in low pO2 conditions was greater in brain of NR than in HR animals. Activity of NADH-cytochrome C reductase (rotenon-sensitive) and Km for NADH in HR brain was more higher in the comparison with NR. These data indicate the main role of NADH-oxidase way in the formation of the individual brain resistance to hypoxia.