【摘要】：目的:研究哮喘大鼠外周血、肺泡灌洗液(BALF)上清液白介素-8(IL-8)、嗜酸性粒細胞趨化因子(Eotaxin)表達水平和肺組織IL-8、Eotaxin mRNA及蛋白表達及地塞米松(DXM)對其影響。 方法:30只雄性SD大鼠隨機分為3組，每組10只：正常組、哮喘組和DXM干預(yù)組。（1）哮喘組：第1天和第8天大鼠腹腔注射1ml OVA1mg和Al(OH)3100mg無菌混懸液致敏。2周后將已致敏大鼠置于自制霧化玻璃箱中，，用1%OVA霧化吸入激發(fā)，1次/天×30min，哮喘大鼠表現(xiàn)為易激怒、呼吸急促、鼻翼煽動、進食差、大小便失禁等癥狀，連續(xù)7天。（2）DXM干預(yù)組于每日激發(fā)前半小時予DXM1mg/kg腹腔注射。（3）正常組：致敏與激發(fā)均用生理鹽水代替。在末次激發(fā)后24小時，處死大鼠，收集血清、肺泡灌洗液（BALF）和肺組織。并將肺組織經(jīng)脫水透明、石蠟包埋等處理后制作成肺標(biāo)本切片。運用ELISA方法對血清和BALF上清液IL-8、Eotaxin水平進行測定，以及用改良牛氏計數(shù)臺對BALF沉淀細胞進行計數(shù)并將沉淀細胞涂片染色后進行分類計數(shù)。觀察各組肺組織病理學(xué)改變。通過RT-PCR方法測定肺組織IL-8、Eotaxin mRNA表達。運用免疫組織化學(xué)方法測定大鼠肺組織標(biāo)本IL-8、Eotaxin蛋白表達。各組指標(biāo)數(shù)據(jù)經(jīng)統(tǒng)計學(xué)方法進行分析比較。 結(jié)果:1.哮喘組大鼠BALF中白細胞總數(shù)，嗜酸性粒細胞、中性粒細胞、淋巴細胞百分比顯著高于正常組(P0.01)；DXM干預(yù)組白細胞總數(shù)和嗜酸性粒細胞、中性粒細胞、淋巴細胞百分比較哮喘組明顯減少(P0.05)，較正常組白細胞總數(shù)、嗜酸性粒百分比明顯增加(P0.01)，但中性粒細胞、淋巴細胞百分比無統(tǒng)計學(xué)意義（P0.05）。 2.哮喘組大鼠血清和BALF上清IL-8、Eotaxin水平均顯著高于正常組(P0.01)，DXM干預(yù)組IL-8、Eotaxin水平明顯低于哮喘組(P0.05)，DXM干預(yù)組IL-8水平明顯高于正常組(P0.05)，Eotaxin水平與正常組無明顯差異（P0.05）。 3.哮喘組大鼠肺組織IL-8、Eotaxin mRNA及蛋白的表達水平明顯高于正常組(P0.01)，DXM組IL-8、Eotaxin mRNA及蛋白的表達與哮喘組相比明顯減少(P0.01)，仍明顯高于正常組(P0.05)。 結(jié)論:趨化因子IL-8和Eotaxin參與了哮喘炎癥過程，DXM可通過抑制IL-8和Eotaxin表達來減弱其對炎性細胞中性粒細胞和嗜酸性粒細胞的趨化與激活從而減輕炎癥反應(yīng)，這可能是DXM減輕哮喘炎癥反應(yīng)的作用機制之一。
[Abstract]:Aim: to study the expression of interleukin-8 (IL-8) and eosinophil chemokine (Eotaxin) in peripheral blood, alveolar lavage fluid (BALF) supernatant of asthmatic rats and the expression of IL-8 eotaxin mRNA and protein in lung tissue, and the effect of dexamethasone (DXM) on the expression of IL-8 eotaxin and protein. Methods 30 male Sprague-Dawley rats were randomly divided into 3 groups, 10 rats in each group: normal group, Asthma group and DXM intervention group. (1) Asthma group: rats were sensitized by intraperitoneal injection of 1ml OVA1mg and Al (OH) 3100mg aseptic suspension on the 1st and 8th day. The asthmatic rats were irritated by 1%OVA atomization inhalation once a day for 30 minutes. The symptoms of asthma rats were irritable, shortness of breath, agitation of nasal wing, poor food intake, incontinence of feces and urine, and so on. (2) DXM intervention group was injected intraperitoneally with DXM1mg/kg half an hour before daily stimulation. (3) normal group: the sensitization and stimulation were replaced by normal saline. The rats were killed 24 hours after the last stimulation, and the serum, alveolar lavage fluid (BALF) and lung tissue were collected. The lung tissue was treated with dehydration and transparency and paraffin embedded. The levels of IL-8 eotaxin in serum and supernatant of BALF were determined by ELISA method, and the precipitated cells of BALF were counted by modified Bull's counter and stained by smear. Lung histopathological changes were observed in each group. The expression of IL-8 eotaxin mRNA in lung tissue was determined by RT-PCR method. The expression of IL-8 eotaxin in rat lung tissue was determined by immunohistochemical method. The index data of each group were analyzed and compared by statistical method. The result is 1: 1. The percentage of leukocytes, eosinophils, neutrophils and lymphocytes in BALF of asthmatic rats was significantly higher than that of control group (P0.01). The percentage of lymphocytes in asthma group was significantly lower than that in asthma group (P0.05), the percentage of total leukocytes and eosinophilic granulocytes was significantly increased (P0.01), but the percentage of neutrophils and lymphocytes had no statistical significance (P0.05). The level of IL-8 eotaxin in serum and supernatant of BALF in asthma group was significantly higher than that in normal group (P0.01). The level of IL-8 eotaxin in DXM intervention group was significantly lower than that in asthmatic group (P0.05). The level of eotaxin in serum and BALF supernatant of asthmatic group was significantly higher than that in normal group (P0.05). The expression of IL-8 eotaxin mRNA and protein in lung tissue of asthmatic group was significantly higher than that of normal group (P0.01) and the expression of IL-8 eotaxin mRNA and protein in DXM group was significantly lower than that in asthmatic group (P0.01), but still significantly higher than that in normal group (P0.05). Conclusion: the chemokines IL-8 and Eotaxin are involved in the inflammatory process of asthma. DXM can attenuate the chemotaxis and activation of inflammatory neutrophils and eosinophils by inhibiting the expression of IL-8 and Eotaxin. This may be one of the mechanisms by which DXM attenuates the inflammatory response of asthma.
【學(xué)位授予單位】：安徽醫(yī)科大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2012
【分類號】：R562.25

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相關(guān)期刊論文 前2條

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