大鼠甲基苯丙胺自身给药行为模型构建

目的獉獉:建立大鼠甲基苯丙胺自身给药行为模型。方法獉獉:训练♂SD大鼠通过鼻触行为进行甲基苯丙胺静脉自身给药,训练期剂量0.03 mg.kg-1或0.06 mg.kg-1。每天进行4 h。固定频率(FR)和渐变频率(PR)测试剂量为0.015、0.03、0.06、0.09和0.12 mg.kg-1)FR和PR测试分别为4 h和6 h。戒断停药2周后,大鼠重新返回实验笼进行消退及复吸测试,包括6个阶段的消退和一个阶段的复吸测试。结果獉獉:训练7 d后,80%的实验大鼠建立稳定的甲基苯丙胺静脉自身给药行为。FR剂量效应曲线是一条下降的曲线,即随着剂量的增加实验大鼠鼻触数降低。PR曲线是一条上升的曲线,即随着剂量的增加实验大鼠断点数逐渐增加。消退和复吸测试中主要测试有效鼻触数。经过6个阶段的消退测试,实验大鼠有效鼻触数下降到3±s 3次。随后经过一个阶段的复吸测试,大鼠有效鼻触数可上升至57±s 8次。结论獉獉:通过自身给药训练实验大鼠成功的获得了甲基苯丙胺的自身给药行为,消退和相关环境线索诱导的复吸模型。

CONSTRUCT THE MODEL OF METHAMPHETAMINE SELF-ADMINISTRATION IN RATS

Objective:To establish the model of methamphetamine self-administration in rats.Methods:Male SD rats were trained to intravenously self-administered methampheta-mine by nose-poking responding.The training doses were 0.03 mg·kg-1 or 0.06 mg·kg-1.Subsequently,the animals self-administered methamphetamine(0.015,0.03,0.06,0.09 and 0.12 mg·kg-1)under the schedule of fixed ratio(FR)and progressive ratio(PR).Each testing session of FR was 4 hours and PR's was 6 hours.Following two-week abstinence,rats were returned to the testing chambers to test extinction and relapse responses.There were a total of 6 extinction sessions and a relapse session.Results:A total of 80% of rats exhibited stable responding of intravenous methamphetamine self-administration following seven days of training.The dose-response curve of FR and PR responding is downward and upward-shift respectively.After two-week abstinence,the animals exhibited extinguished responding and the responding was most prominent during the first extinction session.Finally,the animals showed increased responding of nose poking on the drug-associated side during the period of reinstatement.Conclusion:The animal model of methamphetamine self-administration and relapse was well established in the current studies.