Antidepressant-like activity of tetramethylpyrazine measured by acute and chronic experimental methods in rat model of depression / 中华行为医学与脑科学杂志

ABSTRACT

Objective To study the potential antidepressive-like effect of tetramethylpyrazine (TMP). Methods Forced-swimming and chronic mild stress (CMS) tests were performed to assess the antidepressant-like activity of TMP. Male Sprague-Dawley (SD) strain rats were divided into six matched groups (n= 13 or 14 in each group) based on their sucrose consumptioncontrol, CMS, CMS + fluoxetine, and CMS + TMP groups. The rats except control were housed separately in different rooms, and the rat model of depression was established by exposing to an unpredictable sequence of stressors for 28 days; the rats in CMS + fluoxetine were exposed to CMS and received administration of FLU (2.0 mg· kg-1·d-1 ,ig) for 28 days; the rats in CMS + TMP groups were exposed to CMS and received administration of TMP (10,20,40 mg·kg-1·d-1 ,ig) , respectively, for 28 days. The rats in control group were given ordinary daily care and received ig administration of normal saline simultaneously. The body weight, food intake and fluid consumption were measured, and the behaviors were examined by open field during the duration of the stress procedure, and forced-swimming test was performed 1 day after last unpredictable stressor. Results Acute administration of TMP markedly decreased the duration of immobility during forced-swimming test((89.0 ±37.0)s vs (117.1 ±32. 1)s, P<0.05) . Chronic administration of TMP partially countered the effects of CMS on consumption of sucrose solution and locomotion and exploration behavior, and potently shortened the immobility time during forced-swimming test following CMS in rats. The results showed that long-term administration of TMP partially reversed the effects of CMS on the body weight gain,the consumption of sucrose solution,the squares crossing in open field test and the immobility time during forced-swimming test in rats ((91.9 ±31.5) vs (124.4±27.0)s,P<0.05).Conclusion TMP shows obvious antidepressant-like activity.