摘要
目的:研究戒断后的吗啡依赖大鼠在应激诱导下的位置偏爱行为,并毁损伏隔核(nucleusaccumbens,NAc)观察其对大鼠条件性位置偏爱(conditionedplacepreference,CPP)的影响和NAc在应激诱发复吸中的作用。方法:雄性SD大鼠通过吗啡强化形成CPP后,采用立体定向方法使用直流电选择性毁损NAc犤NAc双侧坐标为:前后(AP)+1.7mm,外侧(L)±1.5mm和背腹(DV)硬膜表面以下7.5mm,毁损电流/时间为2mA/min犦,对照组用相同的过程但不通电流。经过15d的熄灭训练后,给予间断足击应激刺激(电流强度0.5mA,时程0.5s,间隔10～70s,平均40s)诱导大鼠重建位置偏爱行为,测量并比较毁损组与对照组的位置偏爱得分。结果:间断足击应激恢复了对照组大鼠对吗啡的CPP,第25天的CPP得分显著高于第1天犤第25天为(673±53)s;第1天为(446±50)s,q=4.91,P<0.01犦。NAc毁损组大鼠在间断足击应激诱导下未恢复对吗啡的CPP,第25天的CPP得分与第1天差异无显著性意义犤第25天为(471±52)s;第1天为(460±53)s,q=2.82,P>0.05犦。结论:间断足击应激可有效诱导戒断动物复吸,毁损NAc能阻断间断足击应激诱导戒断大鼠重建觅药行为。在应激诱导戒断动物觅药行为中,NAc起重要作用。
AIM:To study the place preference behavior of morphia dependent rats after abstinence,observe its effect on conditioned place preference(CPP) and the role nucleus accumbens plays in footshock induced drug retaking. METHODS:After the male SD rats were successfully trained with morphine into CPP,nucleus accumbens was lesioned with a stereotactic method by direct current(DC)selectively[the bilateral coordinates of nucleus accumbens:anteroposterior(AP)+1.7 mm,lateral (L)±1.5 mm,7.5 mm below the surface of dorsiventral(DV) dura mater, lesion current/duration was 2 mA/min].The control group was treated the same except for current.After a 15 day abstinence period, random intermittent footshock(DC square wave,0.5 mA,0.5 s width,interval 10 70 s)was given to induce the rats to reconstruct the place preference behavior,the place preference score of the two groups were measured and compared. RESULTS:Intermittent footshock reactivated the CPP to morphia of rats in control group, the CPP score of the 25 th day[(673±53) s] was significantly different from that of the 1st day[(446±50)s](q=4.91,P< 0.01).CPP to morphia didn't reactivate after intermittent footshock of the rats in the nucleus accumbens lesion group, the CPP score of the 25 th day[(471±52)s]was not significantly different from that of the 1st day[(460±53)s](q=2.82,P >0.05). CONCLUSION:Intermittent footshock can effectively induce the abstinence of drug retaking of animal, lesion nucleus accumbens can stop the reconstruction of morphia seeking behavior of rats of footshock induced abstinence.Nucleus accumbens plays an important role in stress induced abstinence of the drug seeking behavior in animals.
出处
《中国临床康复》
CSCD
2003年第31期4224-4225,共2页
Chinese Journal of Clinical Rehabilitation
