Downregulation of GRK6 in arcuate nucleus promotes chronic visceral hypersensitivity via NF-κB upregulation in adult rats with neonatal maternal deprivation
Downregulation of GRK6 in arcuate nucleus promotes chronic visceral hypersensitivity via NF-κB upregulation in adult rats with neonatal maternal deprivation
复制标题
弓状核中GRK6的下调通过新生母亲剥夺成年大鼠中NF-κB的上调促进慢性内脏过敏
DOI：
10.1177/1744806920930858
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发表时间：
2020-05-01
期刊：
影响因子：
3.3
通讯作者：
Xu, Guang-Yin
中科院分区：
文献类型：
--
作者：
Li, Xin;Xu, Yu-Cheng;Xu, Guang-Yin
目的弓状核是痛指令形成的重要脑区。G蛋白偶联激酶6（GRK 6）通过G蛋白偶联受体调节信号传导。研究表明GRK 6参与炎症性疼痛和神经病理性疼痛。本研究旨在探讨GRK 6在慢性内脏痛弓状核中的作用及其机制。方法采用新生儿母亲剥夺法复制大鼠慢性内脏痛模型，通过监测大鼠结直肠扩张阈值来评价大鼠慢性内脏痛的发生。采用Western blotting、免疫荧光、实时定量PCR和Nissl染色等方法检测GRK 6和核因子κB（NF-κB）的表达及相互作用。结果与对照组相比，孕鼠弓状核GRK 6的表达明显减少。GRK 6主要表达于弓状核神经元，而在星形胶质细胞中不表达，在小胶质细胞中有少量表达。新生儿母亲剥夺降低弓状核GRK 6阳性神经元的百分比。弓状核慢病毒注射过表达GRK 6可逆转新生母体剥夺大鼠的慢性内脏痛此外，母亲剥夺新生大鼠弓状核NF-κB表达明显上调。NF-κB选择性抑制剂吡咯烷二硫代氨基甲酸酯抑制新生大鼠慢性内脏痛GRK 6和NF-κB B在弓状核神经元表达。更重要的是，GRK 6的过表达在蛋白水平逆转了NF-κB的表达。与此相反，注射吡咯烷二硫代氨基甲酸酯，每天一次，连续7天，并没有改变GRK 6在弓状核的表达，新生儿母亲剥夺大鼠。结论GRK 6可能是慢性内脏痛中枢机制的关键分子，其机制可能与抑制NF-κB信号通路有关。GRK 6的过表达可能是治疗慢性内脏痛的潜在策略。
Aims The arcuate nucleus is a vital brain region for coursing of pain command. G protein-coupled kinase 6 (GRK6) accommodates signaling through G protein-coupled receptors. Studies have demonstrated that GRK6 is involved in inflammatory pain and neuropathic pain. The present study was designed to explore the role and the underlying mechanism of GRK6 in arcuate nucleus of chronic visceral pain. Methods Chronic visceral pain of rats was induced by neonatal maternal deprivation and evaluated by monitoring the threshold of colorectal distension. Western blotting, immunofluorescence, real-time quantitative polymerase chain reaction techniques, and Nissl staining were employed to determine the expression and mutual effect of GRK6 with nuclear factor κB (NF-κB). Results Expression of GRK6 in arcuate nucleus was significantly reduced in neonatal maternal deprivation rats when compared with control rats. GRK6 was mainly expressed in arcuate nucleus neurons, but not in astrocytes, and a little in microglial cells. Neonatal maternal deprivation reduced the percentage of GRK6-positive neurons of arcuate nucleus. Overexpression of GRK6 by Lentiviral injection into arcuate nucleus reversed chronic visceral pain in neonatal maternal deprivation rats. Furthermore, the expression of NF-κB in arcuate nucleus was markedly upregulated in neonatal maternal deprivation rats. NF-κB selective inhibitor pyrrolidine dithiocarbamate suppressed chronic visceral pain in neonatal maternal deprivation rats. GRK6 and NF-κB were expressed in the arcuate nucleus neurons. Importantly, overexpression of GRK6 reversed NF-κB expression at the protein level. In contrast, injection of pyrrolidine dithiocarbamate once daily for seven consecutive days did not alter GRK6 expression in arcuate nucleus of neonatal maternal deprivation rats. Conclusions Present data suggest that GRK6 might be a pivotal molecule participated in the central mechanisms of chronic visceral pain, which might be mediated by inhibiting NF-κB signal pathway. Overexpression of GRK6 possibly represents a potential strategy for therapy of chronic visceral pain.