van Erp Annemoon M M, Miczek Klaus A
Department of Psychology, Bacon Hall, Tufts University, 530 Boston Avenue, Medford, MA 02155, USA.
Psychopharmacology (Berl). 2007 Apr;191(3):679-88. doi: 10.1007/s00213-006-0637-3. Epub 2006 Nov 29.
Alcohol drinking may lead to increased aggression in certain individuals, and both fighting and drinking increase levels of dopamine and serotonin in mesocorticolimbic structures. Assessing the dynamic changes in these neurotransmitters during the course of drinking and fighting has remained challenging.
The objective of the study was to learn about ongoing monoaminergic activity in the nucleus accumbens of rats that engaged in aggressive behavior after having consumed low doses of alcohol.
After male members of breeding pairs of Long-Evans rats displayed reliable aggression toward an intruder into their home cage, they were trained to consume a 10% alcohol solution, leading to blood alcohol levels of 20-80 mg/dl. Subsequently, the effect of daily alcohol self-administration on aggression was determined in biweekly confrontations with an intruder. Finally, rats were implanted with a microdialysis probe aimed at the n. accumbens for sample collection before, during, and after a 10-min alcohol drinking session followed by a 10-min aggressive confrontation.
Accumbal dopamine, but not serotonin, levels tended to increase in anticipation of the daily alcohol session, reaching significance immediately after the alcohol session and remaining significantly elevated (by 40%) during and after the subsequent confrontation. No such changes were seen in residents that confronted an intruder without preceding alcohol consumption. Animals that had a history of becoming more aggressive after consumption of low levels of alcohol showed similar changes in dopamine levels as did animals that had no such history.
The rise in accumbal dopamine confirms previous findings and seems to reflect the anticipation of alcohol consumption; it persisted during the aggressive confrontation regardless of the level of aggression. The daily alcohol drinking for several months may have facilitated dopamine release and masked any further changes associated with the aggressive encounter.
饮酒可能会导致某些个体攻击性增强，而打架和饮酒都会使中脑边缘叶结构中的多巴胺和血清素水平升高。评估饮酒和打架过程中这些神经递质的动态变化一直具有挑战性。
本研究的目的是了解低剂量饮酒后出现攻击行为的大鼠伏隔核中正在进行的单胺能活动。
将长 Evans 大鼠繁殖对中的雄性成员训练至对侵入其家笼的入侵者表现出可靠的攻击性后，训练它们饮用 10%的酒精溶液，使血液酒精水平达到 20 - 80 mg/dl。随后，在每两周与入侵者的对抗中确定每日酒精自我给药对攻击性的影响。最后，在大鼠进行 10 分钟饮酒时段，随后进行 10 分钟攻击性对抗之前、期间和之后，植入一个针对伏隔核的微透析探针用于样本采集。
在每日饮酒时段预期时，伏隔核多巴胺水平有升高趋势，但血清素水平无变化，饮酒时段结束后立即达到显著水平，并在随后的对抗期间及之后仍显著升高（升高 40%）。在未饮酒就与入侵者对抗的大鼠中未观察到此类变化。有低剂量饮酒后攻击性增强历史的动物，其多巴胺水平变化与无此类历史的动物相似。
伏隔核多巴胺水平的升高证实了先前的研究结果，似乎反映了对饮酒的预期；无论攻击程度如何，在攻击性对抗期间该升高一直持续。数月的每日饮酒可能促进了多巴胺释放，并掩盖了与攻击性遭遇相关的任何进一步变化。
Zotero 插件