支气管哮喘发病学简介诱发支气管哮喘的因素,有特异的与非特异的两大类。前者指特异体质的人吸入过敏原后诱发的哮喘;所谓吸入性(外源性)哮喘,多数是第Ⅰ型(速发型)过敏反应的表现。在过敏原的作用下,淋巴细胞产生免疫球蛋白E(IgE),IgE 与呼吸道粘膜的肥大细胞结合,再遇特异的过敏原,即导致肥大细胞脱颗粒,释放出组胺、慢反应物质(SRS—A)等化学介质。这些化学介质作用于支气管腺体、血管和平滑肌,引起呼吸道粘液栓、粘膜水肿和平滑肌痉挛,造成呼吸道狭窄和阻塞,产生喘息症状。当然,变态反应性哮喘不一定都单纯属于速发型过敏,也有证据表明属于Ⅲ型(抗原-抗体复合物型)和Ⅳ型(延迟型)变态反应的。在患者呼吸道反应性增高的基础上,许多物理的、化学的非特异刺激也能诱发哮喘。所谓内因性哮喘,指的就是那部分未能找到过敏原的病人。非特异刺激加诸呼吸道时,兴奋呼吸道的“刺激”感受器,通过迷走神经反射弧,释放乙酰胆碱,同样可引起呼吸道阻 Bronchial asthma pathogenesis Introduction induced bronchial asthma factors, there are two specific and non-specific categories. The former refers to the specific physique of people who inhaled allergens induced asthma; the so-called inhalation (exogenous) asthma, mostly type Ⅰ (type of hair) allergic reactions. In the role of allergens, lymphocytes produce immunoglobulin E (IgE), IgE and respiratory mucosal mast cells, met the specific allergen, which leads to degranulation of mast cells, the release of histamine, slow response substances ( SRS-A) and other chemical media. These chemical mediators act on the bronchial glands, blood vessels and smooth muscles, causing respiratory mucus plug, mucosal edema and smooth muscle spasms that cause narrowing and obstruction of the respiratory tract and wheezing. Of course, allergic asthma is not necessarily a mere hypersusceptible hypersensitivity. There is also evidence of type III (antigen-antibody complex) and type IV (delayed type) allergies. Based on the patient’s increased respiratory reactivity, many physical, chemical non-specific stimuli can also induce asthma. The so-called intrinsic cause of asthma, refers to that part of the patient failed to find allergens. Non-specific stimulation added to the respiratory tract, the excitement of the respiratory “stimulus ” receptors through the vagus reflex arc, the release of acetylcholine, can also cause respiratory resistance