1,25-二羟维生素D3对哮喘豚鼠肥大细胞类胰蛋白酶释放的影响

Effect of 1,25-dihydroxyvitamin D3 on the mact cells tryptase in asthmatic guinea pigs

目的探讨1,25-二羟维生素D3对哮喘豚鼠肥大细胞类胰蛋白酶释放的影响。方法用卵清蛋白(OVA)腹腔注射致敏和雾化吸入激发建立哮喘豚鼠模型。将30只健康豚鼠分为对照组(A组)、哮喘组(B组)、1,25-二羟维生素D3组(C组),每组10只。A、B组予花生油灌胃;C组予1,25-二羟维生素D3融入花生油灌胃。测定哮喘豚鼠呼气相气道阻力(Re),收集支气管肺泡灌洗液(BALF)进行细胞计数;肺组织HE染色和免疫组化观察肺组织病理变化及肥大细胞类胰蛋白酶分布情况。结果 C组Re较B组明显降低(P<0.05)。B组BALF细胞总数、嗜酸性粒细胞比例较A组增高(P<0.05),肺组织炎性病变明显;C组BALF细胞总数、嗜酸性粒细胞比例较B组明显降低(P<0.05),肺组织炎性病变减轻。B组Tryptase阳性细胞较A组明显增多(P<0.05),主要分布在气道黏膜下,肺泡间隔及血管周围;C组Tryptase阳性细胞较B组显著减少。结论 1,25-二羟维生素D3可降低哮喘豚鼠气道阻力,减轻肺组织炎症反应,并可抑制肥大细胞释放类胰蛋白酶。

Objective To observe the effect of 1,25-dihydroxyvitamin D3 on the mast cell tryptase in asthmatic guinea pigs. Methods Asthmatic models in guinea pigs were constructed by immunization of intraperitoneal injection with ovalbumin（OVA）and challenge of inspiration with nebulized OVA. Thirty guinen pigs were divided into control group（group A）, asthmatic group（group B）, 1,25-dihydroxyvitamin D3 group（group C）, 10 cases in each group. Peanut oil were filled stomach in group A and group B, pea nut oil with 1,25 dihydroxy vitamin D3 were filled stomach in group C. The airway responsiveness was detected,and the total cell numbers and classification in bronch-oalveola lavage fluid（BALF） were studied. The lung tissues were stained with Hematoxylin-E- osin to observe the pathologica changes and with anti-human tryptase antibody by using immunohistochemical technique to count the mast cell tryptase. Results The airway responsiveness in group C were significantly lower than in group B（P〈0.05）. The total cell numbers and the percentage of eosinophil of BALF in group B were significantly higher than in group A（P〈0.05） ,and the in- flammation response in lung tissue were significantly slighter; the total cell numbers and the percentage of eosinophil of BALF in group C were significantly lower than group B（P〈0.05） ,lung tissue inflammatory lesions reduced. Tryptase positive cells in group B increased significantly than in group A（P〈0.05）, and mainly distributed in the airway mucosa,the alveolar interval and around blood vessels;Tryptase positive cells in group C reduced significantly than group B. Conclusion 1,25-dihydroxyvitamin D3 could reduce airway responsiveness, obviously relieve inflammation response in airway and lung tissue, and depress mast cell activation also.