Cocaine and Pavlovian fear conditioning: dose-effect analysis.
Cocaine and Pavlovian fear conditioning: dose-effect analysis.
复制标题
可卡因和巴甫洛夫恐惧调节：剂量效应分析。
DOI：
10.1016/j.bbr.2006.10.008
复制
发表时间：
2007
影响因子：
2.7
通讯作者：
Anagnostaras,StephanG
中科院分区：
文献类型：
--
作者：
Wood,SuzanneC;Fay,Jonathan;Sage,JenniferR;Anagnostaras,StephanG
新出现的证据表明，滥用可卡因和其他药物会干扰认知功能的许多方面。作者检测了0.1-15mg /kg可卡因对小鼠巴甫洛夫情境和暗示恐惧条件反射的影响。正如预期的那样，训练前的可卡因剂量依赖性产生了多动症和冷冻中断。令人惊讶的是，当小鼠随后进行停药测试时，与生理盐水对照动物相比，用中等剂量可卡因（15mg/kg）预处理的小鼠表现出明显更少的情境和线索记忆。相反，与对照组相比，用极低剂量的可卡因（0.1mg/kg）预处理的小鼠对情境和音调的恐惧记忆都显着增强。这些结果不是由于可卡因的麻醉作用，因为休克反应性不受可卡因的影响。数据表明，尽管可卡因被认为是一种提高成绩和引起焦虑的药物，但这种效果只在非常低的剂量下才会出现，而中等剂量会破坏海马体和杏仁核依赖的恐惧条件反射。
Emerging evidence suggests that cocaine and other drugs of abuse can interfere with many aspects of cognitive functioning. The authors examined the effects of 0.1–15mg/kg of cocaine on Pavlovian contextual and cued fear conditioning in mice. As expected, pre-training cocaine dose-dependently produced hyperactivity and disrupted freezing. Surprisingly, when the mice were tested off-drug later, the group pre-treated with a moderate dose of cocaine (15mg/kg) displayed significantly less contextual and cued memory, compared to saline control animals. Conversely, mice pre-treated with a very low dose of cocaine (0.1mg/kg) showed significantly enhanced fear memory for both context and tone, compared to controls. These results were not due to cocaine's anesthetic effects, as shock reactivity was unaffected by cocaine. The data suggest that despite cocaine's reputation as a performance-enhancing and anxiogenic drug, this effect is seen only at very low doses, whereas a moderate dose disrupts hippocampus and amygdala-dependent fear conditioning.