Ambulatory activity in streptozotocin-induced diabetic rats

This study was undertaken to investigate changes in ambulatory and drinking behavior, using the Gunma University-type special apparatus for continuous and direct measurement of ambulation and drinking in streptozotocin-induced diabetic rats (STZ, 60 mg/kg). Ambulatory activity of diabetic rats was significantly less than that of control rats during the dark phase but not during the light phase. Ambulatory activity of diabetic rats was also significantly less from 0900 to 1000 hr, but significantly more from 1400 to 1500 hr and 1700 to 1800 hr than that of control rats. On the other hand, there was significant increase in drinking behavior from DM-1W to DM-4W rats throughout the experimental time. Since diabetic animals are very sick, a wide variety of metabolic systems, including dopamine turnover, would be expected to be altered in these animals, and such alterations could also contribute to the results observed. Further studies are in progress to determine whether these abnormalities will be normalized by insulin administration.