TY - JOUR T1 - Effect of repeated morphine and tramadol administration on the motor behavior in the neonatal period TT - JF - Physiol-Pharmacol JO - Physiol-Pharmacol VL - 16 IS - 1 UR - http://ppj.phypha.ir/article-1-790-en.html Y1 - 2012 SP - 86 EP - 94 KW - tramadol KW - rotarod KW - morphine KW - neonatal period N2 - Introduction: Motor behavior and coordination impairment are known side effects of opioid treatment, yet very few studies have investigated the effects of tramadol on motor behavior, or compared its effect with the effect of an opioid. This study investigates the effects of chronic injection of morphine and tramadol on rat motor function during infancy. Methods: Neonate rats (n=56) were randomly divided into three groups. On postnatal days 8-14, one group received saline and two other groups received tramadol and morphine with a dose-dependent manner. On postnatal day 21, each group was divided into subgroups, which received morphine, tramadol or saline again on postnatal days 22-26. Finally, on postnatal days of 22 and 26, the motor behavior was studied. Results: On postnatal day 23, tramadol caused an increase the falling rate from Rotarod (P M3 ER -