Hynes Tristan J, Thomas Catherine S, Zumbusch Alicia S, Samson Anna, Petriman Ioana, Mrdja Una, Orr Angélique, Cutts Emilie, Ruzindana Bruce G, Hazari Alimohamed, Zjadewicz Margaret, Lovic Vedran
Department of Psychology, University of Calgary, Canada; Alberta Children's Hospital Research Institute, University of Calgary, Canada; Hotchkiss Brain Institute, University of Calgary, Canada.
Department of Psychology, University of Calgary, Canada.
Prog Neuropsychopharmacol Biol Psychiatry. 2018 Dec 20;87(Pt A):56-67. doi: 10.1016/j.pnpbp.2017.09.005. Epub 2017 Sep 9.
Many individuals sporadically and circumstantially sample addictive drugs, yet few become addicted. The individual vulnerabilities underlying the development of addiction are not well understood. Correlational findings show that early life adversity is associated with a greater propensity to develop drug addiction. However, the mechanisms by which early life adversity increases addiction vulnerability are unknown. Separate lines of research have found that several traits are associated with addiction. Here, we examined the effects of early life adversity on addiction-related traits in adulthood. We weaned male and female Sprague-Dawley rats (postnatal day - PND21) and randomly assigned them to either a non-adversity group (N-ADV) or an adversity group (ADV). ADV rats experienced adversity from PND 21-35, they were: a) singly housed, b) food restricted for 12h/day, c) subjected to forced-swim sessions, and d) restrained and exposed to predator odour (1h). As adults, rats were tested for impulsivity, anxiety-like behaviour, novelty preference, and attribution of incentive salience to a reward cue. ADV rats showed enhanced novelty preference and attributed greater incentive value to a reward cue. Compared to N-ADV rats, a greater proportion of ADV rats expressed multiple addiction risk traits. Furthermore, fewer ADV rats expressed no addiction risk traits. This effect was most evident in female ADV rats.
许多人偶尔会在特定情况下尝试成瘾性药物，但很少有人会成瘾。成瘾发展背后的个体易感性尚未得到充分理解。相关性研究结果表明，早年逆境与更高的药物成瘾倾向有关。然而，早年逆境增加成瘾易感性的机制尚不清楚。不同的研究方向发现，有几个特质与成瘾有关。在此，我们研究了早年逆境对成年后成瘾相关特质的影响。我们对雄性和雌性斯普拉格-道利大鼠（出生后第21天）进行断奶，并将它们随机分为非逆境组（N-ADV）或逆境组（ADV）。ADV组大鼠在出生后第21至35天经历逆境，它们：a）单独饲养，b）每天食物限制12小时，c）进行强迫游泳训练，d）被束缚并暴露于捕食者气味（1小时）。成年后，对大鼠进行冲动性、焦虑样行为、新奇偏好以及奖励线索的动机显著性归因测试。ADV组大鼠表现出增强的新奇偏好，并赋予奖励线索更高的动机价值。与N-ADV组大鼠相比，更大比例的ADV组大鼠表现出多种成瘾风险特质。此外，表现出无成瘾风险特质的ADV组大鼠更少。这种效应在雌性ADV组大鼠中最为明显。
