Ottenweller J E, Natelson B H, Pitman D L, Drastal S D
Primate Neurobehavioral Unit, VA Medical Center, East Orange, NJ 07019.
Biol Psychiatry. 1989 Dec;26(8):829-41. doi: 10.1016/0006-3223(89)90123-6.
Research in chronic stress has been hampered by the absence of an operational definition for that condition. To explore possible criteria for chronic stress, we repeatedly exposed rats to 2 hr of tail shock per day. After several days, we found elevated prestress corticosterone levels and abnormal behavior, including decreased food consumption, fear-like suppression of activity immediately before stress, greater hesitancy to drop from a suspended wire, and decreased exploratory behavior in a novel environment. A less intensely stressed group of rats also had elevated prestress corticosterone levels, but not the abnormal behaviors that persisted in shocked rats after the stress sessions were discontinued. We propose that abnormalities in both adrenocortical function and behavior are a better marker for chronic stress than abnormalities in either of these systems alone. The animal model we have described may be useful for studying factors that contribute to development of chronic stress or PTSD.
慢性应激的研究因缺乏该病症的操作性定义而受到阻碍。为了探索慢性应激的可能标准，我们每天反复让大鼠接受2小时的尾部电击。几天后，我们发现应激前皮质酮水平升高以及行为异常，包括食物摄入量减少、应激前立即出现类似恐惧的活动抑制、从悬线掉落时更加犹豫，以及在新环境中探索行为减少。一组应激强度较低的大鼠也有应激前皮质酮水平升高的情况，但没有在电击应激停止后仍持续存在于受电击大鼠身上的异常行为。我们提出，肾上腺皮质功能和行为的异常比单独这些系统中的任何一个异常更能作为慢性应激的更好标志。我们所描述的动物模型可能有助于研究导致慢性应激或创伤后应激障碍（PTSD）发展的因素。
