大鼠肺内冷敏感通道受冷空气刺激后增强炎性因子表达的研究

Effect of cold-sensitive channel activity induced by cold air on expression of inflammatory cytokines in rat lungs

目的探讨短时间内反复冷空气吸入刺激对活体动物肺内瞬时受体电位锚蛋白1(TRPA1)相关炎性因子的影响。方法雄性Wistar大鼠20只,随机分为对照组、冷空气吸入组、暖空气吸入组和激动剂刺激组,每组5只。冷空气吸入组在麻醉后经口气管插管,接气体温度可控吸入装置,吸入(2±1)℃冷空气;暖空气吸入组予以相同处置下吸入(36±1)℃暖空气,每组均处置3次,1 h/次,两次间隔12 h;激动剂刺激组为室温(24±2)℃情况下雾化吸入60 mmol/L丙烯醛,分3次,1 h/次,两次间隔12 h。在最后一次处置结束后活杀大鼠,提取气管及左上肺组织的总RNA,采用PCR方法明确肺TRPA1的表达后,观察反复短时间冷空气吸入刺激对大鼠肺内TRPA1通道相关炎症细胞炎性因子白介素1β(IL-1β)、白介素5(IL-5)、中性粒细胞趋化因子(CXCL-1/KC)mRNA表达的影响。结果 TRPA1在大鼠肺组织中有表达,短时程冷空气刺激组大鼠肺组织的IL-1β、IL-5、CXCL-1/KC mRNA的表达量均较暖空气吸入组及正常对照组升高,TRPA1通道阳性激动剂丙烯醛吸入组也出现相似结果。结论在活体动物层次上,当肺部受到短时有害低温(低于17℃)刺激后,通过TRPA1活化途径使肺内一些炎性因子表达增加。

Objective To investigate the effect of rapid repeated cold air inhalation stimulation on cold-sensitive chan- nel transient receptor potential ankyrin 1 （TRPA1） associated inflammatory cytokines in living lungs. Methods A total of 20 male Wistar rats were randomly and evenly divided into 4 groups：cold air inhalation group, warm air inhalation group, TRPA1 channel agonist inhalation group and normal group, respectively. Tracheal intubation was carried out after anesthesia in rats of cold air inhalation group, and the tubes were linked to the air temperature controlled device with the temperature controlled at （ 2 ＋ 1 ） ~C. The rats of warm air inhalation group were treated in the same way as cold air inhalation group except for the temperature at （36 -＋ 1 ） ~C. The rats of both groups were treated for 3 times, 1 hour each time. There were 12 hour intervals between treatments. The rats of TRPA1 channel agonist inhalation group were treated with atomizing inhalation of 60 mmol/L acrolein at room temperature （24 ＋ 2） ~C for 3 times, 1 hour each time. There were 12 hour intervals between two treatments. The rats were sacrificed after the last treatment. The tracheas and left lung tissues of all rats were taken and total RNA was extracted. The mRNA expressions of TRPA1, interleukin 1 beta （IL-I[3）, interleukin 5 （ IL-5 ）, and neutrophil chemoattractant chemokine （ CXCL-1/KC ） in the rat lungs were detected by real-time quantitative PCR. Results TRPA1 was expressed in rat lung tissues. In the short term cold air inhalation group, the expressions of IL-113 ,IL-5 and CXCL-1/KC mRNA in the rat lungs were higher than those of the warm air inhalation or the normal groups. Similar results were also found in the specific TRPA1 channel positive agonist （acrolein） inhalation group. Conclusion In living animals, the TRPA1 channels of the lungs can be activated by short-term cold air（ 〈 17℃ ） , which results in the increasing expression of some inflammatory cytokines in lungs.