کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5815031 | 1556647 | 2013 | 13 صفحه PDF | دانلود رایگان |
Plastic changes in the amygdala and limbic cortex networks have been widely shown in chronic pain. We have here investigated the role of group I metabotropic glutamate receptors (mGluRs) in the basolateral amygdala (BLA) pre-infra-limbic (PL-IL) divisions of the medial prefrontal cortex (mPFC) neuron connections after carrageenan-induced inflammatory pain in the rat. Intra-plantar injection of carrageenan decreased either spontaneous or mechanically/electrically evoked activity of PL cortex pyramidal neurons which responded with excitation in a way prevented by CPCOOEt, a selective mGluR1 antagonist, though not by MPEP, a selective mGluR5 antagonist. Accordingly, intra-BLA microinjection of DHPG, a group I mGluR agonist, caused PL cortex neuron activity depression, antagonized by CPCCOEt. CPCOOEt, but not MPEP, reduced also carrageenan-induced mechanical allodynia. The PL cortex cell deactivation in inflammatory pain condition was associated with increased GABA (conversely glutamate was decreased) in the PL/IL cortex. The local application of bicuculline, a GABAA receptor selective antagonist, reduced mechanical allodynia. An over-expression of mGluR1, but not mGluR5, have been observed in the PL-IL cortex after inflammatory pain suggesting an increased mGluR1-dependent cross-talk among BLA and IL-PL cortex neurons in inflammatory pain conditions.This article is part of a Special Issue entitled 'Metabotropic Glutamate Receptors'.
⺠Inflammatory pain leads to cortical impairment. ⺠mGluR1 has key role in BLA-driven mPFC deactivation. ⺠Inflammation-induced mPFC deactivation is associated with allodynia. ⺠Mechanical allodynia is reduced by mGluR1 antagonist injected into the amygdala. ⺠Mechanical allodynia is reduced by GABAA antagonist injected into the cortex.
Journal: Neuropharmacology - Volume 66, March 2013, Pages 317-329