目的观察完全弗氏佐剂(complete Freund′s adjuvant,CFA)诱导的小鼠慢性炎症性疼痛模型中,单核细胞趋化因子(monocyte chemoattractant protein-1,MCP-1)及其受体CCR2在杏仁核脑区(the central nucleus of the amygdala,CeA)中的表达...目的观察完全弗氏佐剂(complete Freund′s adjuvant,CFA)诱导的小鼠慢性炎症性疼痛模型中,单核细胞趋化因子(monocyte chemoattractant protein-1,MCP-1)及其受体CCR2在杏仁核脑区(the central nucleus of the amygdala,CeA)中的表达变化以及细胞定位情况。方法足底皮下注射CFA 20μL,制作慢性炎症性疼痛模型,用行为学方法检测小鼠的机械性刺激缩爪阈值和热刺激缩爪潜伏期的变化;用real-time PCR法检测造模后不同时间点CeA中MCP-1/CCR2mRNA的表达变化;用Western blot法检测造模后不同时间点CeA中CCR2蛋白的表达变化;选择CFA 7天组,用免疫荧光染色来观察CeA中MCP-1/CCR2蛋白的表达情况,并用双标染色来定位表达MCP-1/CCR2的细胞类型。结果造模1h后小鼠同侧后爪机械性缩爪阈值和热缩爪潜伏期显著降低(P<0.001),并能维持7天以上;造模1天后,CeA中MCP-1mRNA表达量增加(P<0.05),7天达高峰(P<0.01),一直持续到14天(P<0.05);CCR2mRNA从造模6h起表达增加(P<0.05);Western blot结果显示CeA中CCR2蛋白在造模后各个时间点均有表达上调,7天达高峰(P<0.01),一直持续到14天(P<0.01);免疫荧光染色显示,CFA 7天组CeA中MCP-1/CCR2蛋白的表达与生理盐水对照组相比均有增加,而且荧光双标染色显示MCP-1/CCR2蛋白主要与神经元核标记物(NeuN)共标。结论足底皮下注射CFA能诱导小鼠产生机械性触诱发痛和热痛觉过敏,CeA中MCP-1/CCR2mRNA和蛋白表达均增加,且均在神经元表达,提示该部位表达增加的MCP-1/CCR2可能参与炎症性疼痛的维持过程。展开更多
Restraint water-immersion stress(RWIS), a compound stress model, has been widely used to induce acute gastric ulceration in rats. A wealth of evidence suggests that the central nucleus of the amygdala(CEA) is a focal ...Restraint water-immersion stress(RWIS), a compound stress model, has been widely used to induce acute gastric ulceration in rats. A wealth of evidence suggests that the central nucleus of the amygdala(CEA) is a focal region for mediating the biological response to stress. Different stressors induce distinct alterations of neuronal activity in the CEA; however, few studies have reported the characteristics of CEA neuronal activity induced by RWIS. Therefore, we explored this issue using immunohistochemistry and in vivo extracellular single-unit recording. Our results showed that RWIS and restraint stress(RS) differentially changed the c-Fos expression and firing properties of neurons in the medial CEA. In addition,RWIS, but not RS, induced the activation of corticotropinreleasing hormone neurons in the CEA. These findings suggested that specific neuronal activation in the CEA is involved in the formation of RWIS-induced gastric ulcers.This study also provides a possible theoretical explanation for the different gastric dysfunctions induced by different stressors.展开更多
基金supported by the National Natural Science Foundation of China (31571104 and 81501149)the Science and Technological Project of Shandong Province of China (2016GSF201058)
文摘Restraint water-immersion stress(RWIS), a compound stress model, has been widely used to induce acute gastric ulceration in rats. A wealth of evidence suggests that the central nucleus of the amygdala(CEA) is a focal region for mediating the biological response to stress. Different stressors induce distinct alterations of neuronal activity in the CEA; however, few studies have reported the characteristics of CEA neuronal activity induced by RWIS. Therefore, we explored this issue using immunohistochemistry and in vivo extracellular single-unit recording. Our results showed that RWIS and restraint stress(RS) differentially changed the c-Fos expression and firing properties of neurons in the medial CEA. In addition,RWIS, but not RS, induced the activation of corticotropinreleasing hormone neurons in the CEA. These findings suggested that specific neuronal activation in the CEA is involved in the formation of RWIS-induced gastric ulcers.This study also provides a possible theoretical explanation for the different gastric dysfunctions induced by different stressors.
