Seasonal regulations of resting metabolic rate and thermogenesis in striped hamster (Cricetulus barabensis)

(1)Resting metabolic rate (RMR), nonshivering thermogenesis (NST) and mitochondria cytochrome c oxydase (COX) activity of brown adipose tissue (BAT), as well as weight of skin and fur were measured in striped hamsters (Cricetulus barabensis) that were live-trapped in the summer, autumn, winter and spring.(2)There were significant seasonal effects on thermogenesis and weight of skin and fur. Winter hamsters had higher thermogenic capacity indicative of increased RMR, NST and BAT COX activity, and heavier skin and fur than summer individuals.(3)The data suggest that striped hamsters have developed strategies to adapt to a marked change in the seasonal temperature, including enhancement in resting metabolic rate, capacity to increase NST, and improved insulation in the winter.