Matthews Douglas B, Morrow A Leslie, O'Buckley Todd, Flanigan Timothy J, Berry Raymond B, Cook Melloni N, Mittleman Guy, Goldowitz Dan, Tokunaga Sayaka, Silvers Janelle M
Department of Psychology, University of Memphis, Memphis, TN, USA.
Alcohol. 2008 Sep;42(6):469-76. doi: 10.1016/j.alcohol.2008.05.001. Epub 2008 Jul 2.
Stress is an often-reported cause for alcohol consumption in humans. Acute intermittent footshock is a frequently used paradigm to produce stress in laboratory animals including mice. The effect produced by intermittent footshock stress on ethanol self-administration has been inconsistent: both increases and decreases in ethanol consumption have been reported. The current set of studies further investigates, in three commonly studied mouse strains, the effect of footshock stress on ethanol self-administration. Furthermore, the effect of footshock on plasma corticosterone levels was determined to investigate potential biochemical correlates. Adult male C57BL/6J, DBA/2J, and A/J mice were allowed to self-administer 10% (wt/vol) ethanol for 12 days in a standard 23-h two-bottle paradigm before receiving either 15 min of mild inescapable footshock or no footshock. Shock intensity was equal to the mean intensity at which each strain vocalized as previously determined. Following footshock, animals had the opportunity to self-administer ethanol for an additional 23 h. Separate animals were subjected to either footshock or no shock prior to collection of plasma for corticosterone. Mild footshock stress altered ethanol self-administration and increased plasma corticosterone levels in C57BL/6J mice. Footshock stress did not alter ethanol self-administration or plasma corticosterone levels in DBA/2J or A/J mice. These data demonstrate that mild footshock stress is a suboptimal method of modeling the stress-induced increases in ethanol consumption often reported by humans.
压力是人类饮酒的常见原因。急性间歇性足部电击是在包括小鼠在内的实验动物中产生压力的常用范式。间歇性足部电击应激对乙醇自我给药的影响并不一致:乙醇消耗量的增加和减少均有报道。当前的这组研究进一步在三种常用的小鼠品系中研究了足部电击应激对乙醇自我给药的影响。此外,还测定了足部电击对血浆皮质酮水平的影响,以研究潜在的生化相关性。成年雄性C57BL/6J、DBA/2J和A/J小鼠在标准的23小时双瓶范式中被允许自我给药10%(重量/体积)乙醇12天,然后接受15分钟的轻度不可逃避足部电击或不进行足部电击。电击强度等于先前确定的每个品系发声时的平均强度。足部电击后,动物有机会再进行23小时的乙醇自我给药。在采集血浆用于检测皮质酮之前,将单独的动物分为接受足部电击组或不接受电击组。轻度足部电击应激改变了C57BL/6J小鼠的乙醇自我给药,并增加了其血浆皮质酮水平。足部电击应激并未改变DBA/2J或A/J小鼠的乙醇自我给药或血浆皮质酮水平。这些数据表明,轻度足部电击应激是模拟人类常报道的应激诱导乙醇消耗量增加的次优方法。