Chronic stress increases pain sensitivity via activation of the rACC-BLA pathway in rats.

Chronic stress increases pain sensitivity via activation of the rACC-BLA pathway in rats. Exp Neurol. 2018 Dec 23;: Authors: Liu LY, Zang RL, Chen L, Zhao HY, Cai J, Wang JK, Guo DQ, Cui YJ, Xing GG Abstract Exposure to chronic stress can produce maladaptive neurobiological changes in pathways associated with pain processing, which may cause stress-induced hyperalgesia (SIH). However, the underlying mechanisms still remain largely unknown. In previous studies, we have reported that the amygdala is involved in chronic forced swim (FS) stress-induced depressive-like behaviors and the exacerbation of neuropathic pain in rats, of which, the basolateral amygdala (BLA) and the central nucleus of the amygdala (CeA) are shown to play important roles in the integration of affective and sensory information including nociception. Here, using in vivo multichannel recording from rostal anterior cingulate cortex (rACC) and BLA, we found that chronic FS stress (CFSS) could increase the pain sensitivity of rats in response to low intensity innoxious stimuli (LIS) and high intensity noxious stimuli (HNS) imposed upon the hindpaw, validating the occurrence of SIH in stressed rats. Moreover, we discovered that CFSS not only induced an increased activity of rACC neuronal population but also produced an augmented field potential power (FPP) of rACC local field potential (LFP), especially in low frequency theta band as well as in high frequency low gamma ...
Source: Experimental Neurology - Category: Neurology Authors: Tags: Exp Neurol Source Type: research