阻断阿片受体可改变吗啡成瘾大鼠下边缘皮质脑电功率谱成分

Antagonism of opiate receptor by naloxone could change the infralimbic cortical EEG power spectrum components in morphine addicted rats

旨在探讨纳洛酮阻断阿片受体后吗啡成瘾大鼠前额叶下边缘皮质脑电功率谱的变化。成年雄性Wistar大鼠接受每48 h固定剂量吗啡(10 mg/kg)或生理盐水交替注射连续8 d,经戒断实验和条件性位置偏爱(conditioned place preference,CPP)实验确认建立吗啡成瘾模型;然后记录CPP大鼠麻醉状态前额叶下边缘皮质EEG,分析注射阿片受体拮抗剂纳洛酮前后的EEG功率谱成分。结果发现纳洛酮可使吗啡成瘾大鼠EEG功率谱theta频段功率(P<0.01)和占总功率的比例(P<0.05)显著升高,gamma频段功率也显著升高(P<0.05)。结果表明纳洛酮阻断阿片受体可改变吗啡成瘾大鼠前额叶下边缘皮质EEG功率谱成分。

The purpose of present study is to investigate the effect of antagonism of opiate receptor by naloxone on the prefrontal infral-imbic cortical EEG power in morphine addicted rat.Forty adult male Wistar rats were treated with morphine （10 mg/kg, sc.） every 48 h for consecutive 8 d to establish addicted rat model.The model had been confirmed by withdrawal test and conditioned place prefer-ence （ CPP） test.Then the EEG signals were recorded from the infralimbic cortex （ ILC） （ one subarea of the prefrontal cortex） in an-esthetized CPP rats.Results showed that 30 min after naloxone injection, the EEG powers of theta band （4-7 Hz） and 2 gamma bands （30-49 Hz and 51-100 Hz） and the percentage of theta band in morphine rats increased significantly （All P 〈0.05）.In conclusion, present study indicated that antagonism of opiate receptor by naloxone could enhance the ILC EEG power of theta band and gamma band in morphine addicted rats, and the EEG power changing would be an electrophysiological index of ILC cognitive function and ad-dictive behaviors.