Scientific publications

Hibernation, which allows animals to survive when exposed to low temperatures and lack of food, is a physiological adaptation involving reduced metabolism, heart rate and significant decrease in oxygen consumption. It is believed that the main factor for this adaptation, which enables cell protection against ROS by lowering their generation, may be intensification of antioxidant mechanisms. Still little is known about the antioxidant system of bats. Our aim was to study the retinol and α-tocopherol content in the tissues of 5 species of hibernating bats that live and spend the winter in the northern periphery of their distribution ranges. These data suggest that the retinol and tocopherol content in bats during hibernation was high enough to enable their survival despite the prolonged deprivation of obligate antioxidants, while maintaining the reserves necessary for reproduction. The residual content of α-tocopherol and retinol by spring was the highest in the northern bat, who lost less weight during the period of hibernation than other species. At the same time, females of other species also had quite significant reserves of these vitamins in their tissues in spring, especially so in Brandt’s bats. Analysis of individual data showed that the content of retinol and tocopherol in bats was sex-specific –it was higher in females than in males. There was significant variation of the indices in all the species, which can be explained both by species- and individual differences in the degree of vitamins accumulation before hibernation.