Effect of different conditions of acute exposure to carbon monoxide on the cerebral high-energy phosphates and ultrastructure of brain mitochondria in rats.

Rats were exposed to carbon monoxide (CO) in different conditions: 4 min at 1.3% CO, 40 min at 0.5% CO or 12 h at 0.13--0.15% CO. After 4 min exposure to 1.3% CO the brain content of ATP and PC was substantially reduced; after 40 min exposure to 0.5% CO the cerebral ATP level was slightly increased, whereas the content of both ATP and PC in the brain of rats exposed to CO for 12 h was significantly higher than in the controls. The decrease in the brain level of ATP and PC after 4 min exposure to 1.3% CO was accompanied by ultrastructural changes of mitochondria. No evident differences in the level of cerebral high-energy phosphates were found between rats intoxicated with CO and rats subjected to experimental hypoxemia.