Effects of Ligustilide on the withdrawal syndromes and monoamine neurotransmitters in brain of morphine-dependent rats

Abstract

Objective To investigate the effects of Ligustilide on the withdrawal syndromes syndromes and monoamine neurotransmitters of hypothalamus and nucleus accumbens in morphine-dependent rats. Methods Totally 60 SD rats were divided into control group, model group, clonidine group and Ligustilide high(80 mg/kg), medium(40 mg/kg) and low(20 mg/kg) dose group according to the random number table with 10 in each group.Rats were given in gradual increasing doses of morphine to produce physical dependence.Morphine withdrawal syndrome was precipitated by naloxone and withdrawal symptoms were evaluated by Ryuta Tomoji score.The level of norepinephrine(NE), dopamine (DA)and 5-hydroxytryptamine (5-HT) in rats were tested with enzyme-linked immunosorbent assay(ELISA). Results The total score of somatic withdrawal syndromes in the control group, model group, clonidine group and Ligustilide low, medium and high dose group were 0, (31.83±7.33), (17.92±6.88), (25.58±5.99), (19.88±4.82) and (16.75±4.01) .Compared with the model group, the morphine withdrawal syndromes scores of Ligustilide low, medium and high dose groups and clonidine group were reduced(all P<0.05). The level of NE, DA and 5-HT in hypothalamus and nucleus accumbens were increased compared with that of control group.Compared with the model group, the level of NE, DA and 5-HT in hypothalamus and nucleus accumbens of Ligustilide low, medium and high dose groups and clonidine group were significantly reduced (P<0.05). Conclusion Ligustilide can effectively alleviate the symptoms in morphine-withdrawal rats, which may be related to the inhibition of excessive release of monoamine neurotransmitters in hypothalamus and nucleus accumbens. Key words: Ligustilide; Rats; Morphine withdrawal; Monoamine neurotransmitters