抗原致敏人支气管平滑肌β_2受体-腺苷酸环化酶偶联失常

Abnormality of coupling between β 2 receptor and adenylyl cyclase in isolated human bronchi passively sensitized by allergen

目的：观察抗原刺激是否引起被动致敏的离体人支气管β２受体－腺苷酸环化酶偶联失常。方法：内径２～４ｍｍ的支气管来源于１２例接受肺叶切除手术的病人，用高效价的抗屋尘螨－ＩｇＥ血浆致敏支气管。正常被动致敏及抗原刺激后的支气管分别用于建立腺苷酸环化酶兴奋剂Ｆｏｒｓｋｏｌｉｎ和β２受体兴奋剂舒喘灵累加浓度反应曲线。结果：与正常及被动致敏的支气管比较，抗原刺激后的支气管舒喘灵的反应减弱，而对Ｆｏｒｓｋｏｌｉｎ的反应无明显变化。

Objective: To determine if allergen challenge can result in the abnormality of coupling between β 2 receptor and adenylyl cyclase (AC) in isolated passively sensitized human bronchi. Methods: Bronchus rings of 2-4 mm in diameter were obtained from 12 patients undergoing lobectomy. Passive sensitization of human bronchi was induced with the serum containing high level of IgE to house dust mite. The control, sensitized and allergen challenged rings were used to establish the cumulative concentration response curves to β 2 receptor simulant, salbutamol and forskolin that is an AC activator. Results: The relaxant response to salbutamol was reduced but the relaxant effect to forskolin remained unchanged in the challenged rings as compared with those in the control and passively sensitized rings. Conclusion: Dysfunction of β 2 receptor due to allergen in passively sensitized human bronchus rings is related to abnormality of coupling between β 2 receptor and AC.