Abstract
Recent instruments for the study of thermoregulation in rodents are usually large and often require troublesome trainings of animals. In this study, we designed, made and tested a new simple instrument for investigating rodents' behavioral thermoregulation. The apparatus was composed of two stainless-steel hollow plates (plate A and plate B) with a length of 20cm and width of 5cm. Each plate had an inlet and an outlet that were connected to a separate constant-temperature bath (bath 1 and bath 2). The water temperatures of the baths were controlled at one designated temperature within 10 and 45 degrees and pumped into the plates. A change switch for the water supply was inserted between both the plates and the baths. In the normal switch position, bath 1 supplied water plate A, and bath 2 supplied water plate 2, and in the reverse position, vice versa. Plates A and B were arranged and covered with a surrounding transparent fence 20cm high in a climatic chamber. A rodent stayed inside the fence and moved on plate A or plate B. The position of the rodent was observed by a video camera. We tested thermoregulatory behavior of eight male mice using this instrument. By shuffling the plate temperatures between 10 and 45 degree, the mice moved to the plates with a temperature close to the 35 degree. The findings implied our instrument might be useful as an apparatus for the study of behavioral thermoregulation. [J Physiol Sci. 2006;56 Suppl:S227]