[Effects of forced exercise on withdrawal syndrome, brain hippocampus neurons count and level of serum corticosterone in morphine addicted male rats]

ABSTRACT

Addiction to morphine impairs the behavioral and cognitive performances. The aim of the present study was to evaluate the effects of forced exercise [treadmill] on withdrawal signs after morphine deprivation, serum corticostrone level, and hippocampus neurons count in brain hemisphers in rats addicted to morphine. Adult male Wistar rats were divided into five groups with 10 in each 1] exercised control [C+E], 2] sham exercised control [C+Sh.E], 3] addicted [A], 4] exercised addicted [A+E], and 5] sham-exercised addicted [A+Sh.E]. Withdrawal signs such as number of jumping, teeth chattering, wet-dog shaking, defecation, body scratching, and standingas number of were counted during 30 minutes after naloxone administration. Animals in exercised groups ran on treadmill one hour daily from 9-10 Am in the morning for ten consecutive days. Sham-exercised groups passed same times on turned off treadmill while its shock delivered system was turned on. At the end of experiments serum corticostrone level and hippocampus neurons count were done after decapitation the animals in all groups. The data were analyzed with one-way ANOVA that followed by LSD post hoc test. The differences between groups were accepted as significant with P value less than 0.05. Addiction to morphine increased withdrawal signs and corticostrone secretion significantly and reduced hipocampal neurons in brain, All off which were significant. Forced exercise could inhibit certain withdrawal signs induced by morphine deprivation in addicted rats while could not reverse increased corticostrone level and decreased hippocampus neurons. Despite of useful effects of forced exercise on health conditions and especially cognition during aging, it would cause impair severely some neurobehavioral and hormonal disorders in addicted rats to morphine