Neurobiology of Alcohol Section, Department of Neuroscience, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.
Behav Brain Res. 2010 Jul 29;211(1):58-63. doi: 10.1016/j.bbr.2010.03.008. Epub 2010 Mar 7.
Contexts associated with the availability of alcohol can induce craving in humans and alcohol seeking in rats. The opioid antagonist naltrexone attenuates context-induced reinstatement (renewal) of alcohol seeking and suppresses neuronal activation in the basolateral amygdaloid complex and dorsal hippocampus induced by such reinstatement. The objective of this study was to determine whether pharmacological blockade of opioid receptors in the basolateral amygdala or dorsal hippocampus would attenuate the context-induced reinstatement of alcohol seeking. Rats were trained to self-administer alcohol in one context (Context A), extinguished in a distinct context (Context B) and then tested for reinstatement of alcohol seeking in A and B contexts. Prior to the test session, rats were bilaterally microinjected with 0, 333 or 1000ng (total) naloxone methiodide into the basolateral amygdala or dorsal hippocampus. Naloxone methiodide in the amygdala, but not the hippocampus, dose dependently suppressed context-induced reinstatement. This suggests that opioid transmission in the basolateral amygdaloid complex is an important mediator of context-induced alcohol seeking.
与酒精供应相关的环境会在人类中引起对酒精的渴望，并在大鼠中引起对酒精的寻求。阿片受体拮抗剂纳曲酮可减弱环境诱导的酒精寻求的复燃（恢复），并抑制这种复燃引起的外侧杏仁核复合体和背侧海马中的神经元激活。本研究的目的是确定在外侧杏仁核或背侧海马中阻断阿片受体是否会减弱酒精寻求的环境诱导复燃。大鼠在一个环境中接受酒精自我给药训练（环境 A），在另一个不同的环境中消退（环境 B），然后在 A 和 B 环境中测试酒精寻求的复燃。在测试前，大鼠双侧微注射纳洛酮甲碘化物 0、333 或 1000ng（总量）进入外侧杏仁核或背侧海马。阿片在杏仁核而不是海马中的传递，以剂量依赖的方式抑制了环境诱导的复燃。这表明外侧杏仁核复合体中的阿片传递是环境诱导的酒精寻求的重要介导者。
