Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
Turk J Med Sci. 2016 Dec 20;46(6):1915-1925. doi: 10.3906/sag-1507-7.
BACKGROUND/AIM: The basolateral amygdala (BLA) modulates memory for emotional events and is involved in both stress and memory. This study investigated different durations of stress and the role of BLA on serum corticosterone level and spatial and cognitive memory.
Different durations of stress (acute, mid, and chronic stress), with and without BLA lesion were induced in rats by 6 h/day restraint stress for 1, 7, and 21 days. Memory functions were evaluated by novel object recognition (NOR) and object location test (OLT).
The OLT findings showed locomotor activity and spatial memory slightly decreased with different durations of stress. The NOR findings significantly showed locomotor activity impairment in different durations of stress. Cognitive memory deficit was observed in mid stress. The corticosterone level significantly increased in the mid and chronic stress groups. Moreover, the mid stress was the strongest stress condition. There is a possibility that different stress durations act by different mechanisms. The recognition of a novel location decreased in all lesion groups. It was more severe in the NOR. The BLA lesion significantly decreased corticosterone level in the mid and chronic stress groups compared to similar groups without lesion.
The BLA lesion caused more damage to cognitive than spatial memory in stressed groups.
背景/目的：基底外侧杏仁核（BLA）调节对情绪事件的记忆，并且参与应激和记忆。本研究探讨了不同时长的应激以及 BLA 对血清皮质酮水平以及空间和认知记忆的作用。
通过每天 6 小时的束缚应激，在大鼠中诱导不同时长的应激（急性、中期和慢性应激），并伴有或不伴有 BLA 损伤，持续 1、7 和 21 天。通过新物体识别（NOR）和物体位置测试（OLT）评估记忆功能。
OLT 结果显示，不同时长的应激导致运动活性和空间记忆略有下降。NOR 结果显示，不同时长的应激显著导致运动活性受损。中期应激出现认知记忆缺陷。中期和慢性应激组的皮质酮水平显著升高。此外，中期应激是最强的应激条件。不同的应激时长可能通过不同的机制起作用。在所有损伤组中，对新位置的识别减少，在 NOR 中更为严重。与无损伤的类似组相比，BLA 损伤导致中期和慢性应激组的皮质酮水平显著降低。
BLA 损伤导致应激组的认知记忆比空间记忆受到更大的损害。
