Abstract
Eight, 20 and 31 mo. old male C57BL/6N mice were exposed to three 24-h restraint sessions/wk, or to a nontreatment condition. All mice received five 2-min open field tests after both 5 and 6 wk of treatment. The activity of restrained mice was greater than that of nonrestrained animals. The 8 mo. old mice were more active than older subjects. Age related activity decrements were prominent in the 1st series of open field tests, while restraint effects were most pronounced in the 2nd series.