In 14-day-old Wistar rats (of our own breed) several experiments were performed in which the possible protective significance of hypothermia against oxygen insufficiency (brain cortex) was examined. The aim of this study was to determine the following metabolic parameters: lactate, pyruvate, glucose, calcium, pH and malonyldialdehyde (MDA). 10% homogenates of brain cortex were incubated for 30 min. at 38 °C (control values) and under hypothermia (30 °C and 22 °C). The hypothermic conditions significantly decreased the metabolic rate (pyruvate, lactate and glucose concentrations), the lipoperoxidative activities decreased distinctly and showed a beneficial effect on pH values. When rats were (before being killed by decapitation) exposed to hypobaric hypoxia (9000 m, lasting 30 min.), the results were less distinct and not so unambiguous. A favourable effect of hypothermic conditions on pH values, partially on lipoperoxidative activities and calcium concentration (lower release) as well as on metabolic rate was described.

        Key words: hypothermia, hypoxia, developmental process, brain cortex