[Dangers of postischemic cerebral hyperemia]

The authors draw attention to the danger of the development of hyperaemia because of the possible influence of free oxygen radicals during the hypoxic period on brain cells. Using radioactive microparticles of 85Sr the authors assessed the cardiac minute volume and blood flow through the medulla oblongata, cerebellum, subcortical area and cerebral cortex in adult laboratory rats 20 hours after 2-minute ischaemia induced by positive radial acceleration of 10 G. The results indicate an increase of the local blood supply in the investigated parts of the brain, although lower than after 8-hour exposure to high altitude hypoxia at 7000 m.