Copper-zinc containing and manganese containing superoxide dismutase in the ground squirrel/Citellus citellus/--the effect of hibernation.

The distribution of Copper-Zinc containing and Manganese-containing superoxide dismutase in the liver, kidney, interscapular brown adipose tissue (IBAT) and brain of the ground squirrel, as well as the effect of hibernation, was studied. Activity of both forms of SOD was highest in the liver and lowest in the brain. Activity of the Mn SOD in relation to total SOD was higher in the liver and kidney of the ground squirrel as compared with results reported for other rodents. The highest activity of Mn SOD in relation to total SOD was found in the IBAT and brain (36% and 49%, respectively). Total SOD activity per mg proteins and per g wet mass in IBAT and brain of hibernating animals was increased: for IBAT, p less than 0.05 and p less than 0.025, respectively; for brain, p less than 0.01 and p less than 0.025, respectively. Protein content in hibernating ground squirrel was not significantly changed. In the hibernating ground squirrel CuZn SOD activity in IBAT and brain was higher as compared with the active animal (p less than 0.025 and p less than 0.005, respectively). In the liver and kidney CuZn SOD was not significantly changed during the hibernation. In the liver and brain of the hibernating animals a lower Mn SOD activity was found (p less than 0.005 and p less than 0.05, respectively).