Chen Chieh V, Chaby Lauren E, Nazeer Sahana, Liberzon Israel
Ann Arbor Veterans Affairs, Ann Arbor, MI, United States.
Department of Psychiatry, University of Michigan, Ann Arbor, MI, United States.
Front Behav Neurosci. 2018 Oct 31;12:247. doi: 10.3389/fnbeh.2018.00247. eCollection 2018.
Evidence for and against adolescent vulnerability to posttraumatic stress disorder (PTSD) is mounting, but this evidence is largely qualitative, retrospective, or complicated by variation in prior stress exposure and trauma context. Here, we examine the effects of development on trauma vulnerability using adult post-natal (PN) day 61, early adolescent (PN23) and mid adolescence (PN34) rats and two types of trauma: an established animal model of PTSD, single prolonged stress (SPS), and a novel composite model-SPS predation (SPSp) version. We demonstrate that early and mid adolescent rats are capable of fear conditioning and fear extinction, as well as extinction retention. Our results also demonstrate that both types of trauma induced a deficit in the retention of fear extinction in adulthood, a hallmark of PTSD, but not after early or mid adolescence trauma, suggesting that adolescence might convey resilience to SPS and SPSp traumas. Across all three life stages, the effects of SPS exposure and a novel predation trauma model, SPSp, had similar effects on behavior suggesting that trauma type did not affect the likelihood of developing PTSD-like symptoms, and that SPSp is a predation-based trauma model worth exploring.
支持和反对青少年易患创伤后应激障碍（PTSD）的证据越来越多，但这些证据大多是定性的、回顾性的，或者因先前应激暴露和创伤背景的差异而变得复杂。在这里，我们使用成年产后（PN）第61天、青少年早期（PN23）和青少年中期（PN34）的大鼠以及两种类型的创伤来研究发育对创伤易感性的影响：一种是既定的PTSD动物模型，单次长时间应激（SPS），以及一种新型复合模型——SPS捕食（SPSp）版本。我们证明，青少年早期和中期的大鼠能够进行恐惧条件反射、恐惧消退以及消退保持。我们的结果还表明，这两种类型的创伤都会导致成年期恐惧消退保持出现缺陷，这是PTSD的一个标志，但在青少年早期或中期创伤后不会出现，这表明青春期可能赋予对SPS和SPSp创伤的恢复力。在所有三个生命阶段，SPS暴露和一种新型捕食创伤模型SPSp对行为的影响相似，这表明创伤类型不会影响出现类似PTSD症状的可能性，并且SPSp是一个值得探索的基于捕食的创伤模型。
