Factors related to capsaicin cough sensitivity in healthy subject

咳嗽反射是抵抗吸入或吸入病原微生物的一种防御机制。我们推测咳嗽反射受损可能与反复肺炎的发生有关，而咳嗽敏感性增强可能与过度咳嗽和慢性咳嗽有关，这是一种有害的症状。咳嗽敏感性的调查是一个重要的问题。为了评估与咳嗽敏感性相关的因素，我们招募了没有呼吸道症状、没有吸烟史、患有呼吸道疾病(包括最近的上呼吸道感染和胃食道反流)以及没有服用ACE抑制剂的健康受试者。到目前为止，对30名受试者的ACE基因多态性、血清ACE活性、诱导痰中P物质浓度以及受试者的背景进行了研究。研究了这些发现与辣椒素咳嗽敏感性之间的相关性。ACE基因多态性分析显示，内含子16插入/插入多态10例，插入/缺失多态12例，缺失/缺失多态8例。在这30例受试者中，血管紧张素转换酶基因多态性、血清血管紧张素转换酶活性、诱导痰中P物质浓度、受试者背景与辣椒素咳嗽敏感性无显著相关性。我们现在正在招募更多的受试者，并正在进行进一步的分析。另一组反复肺炎但没有潜在疾病的受试者接受了咳嗽敏感性检查，并与年龄和性别匹配的对照组进行了比较。与对照组相比，反复肺炎的受试者对辣椒素咳嗽反射不敏感。我们的结论是，咳嗽反射受损可能与复发性肺炎的发生有关。

Cough reflex is a defence mechanism against aspiration or inhalation of pathogenic microorganisms. We hypothesized that impaired cough reflex may be related to the development of recurrent pneumonia, while increased cough sensitivity may be related to excessive cough and chronic cough, which is a noxious symptom. Investigation of cough sensitivity is an important issue.To assess the factors related to cough sensitivity, we have recruited healthy subjects who have no respiratory symptoms, no history of smoking, respiratory diseases including recent upper respiratory infection and gastroesophageal reflux, and who are not taking ACE inhibitors. Thus far, 30 subjects were studied regarding ACE gene polymorphism, serum ACE activity, concentration of substance P in induced sputum, and subjects' backgrounds. Correlations between these findings and capsaicin cough sensitivity were examined. Analysis of ACE gene polymorphism revealed that insertion/insertion polymorphism at intron 16 was found in 10 subjects, insertion/deletion polymorphism in 12 subjects, and deletion/deletion polymorphism in 8 subjects. In these 30 subjects, there were no significant correlations between the ACE gene polymorphism, serum ACE activity, concentration of substance P in induced sputum, subjects' backgrounds and capsaicin cough sensitivity. We are now recruiting more subjects and are further analyzing.Another subjects group with recurrent pneumonia but no underlying condition was examined about cough sensitivity and was compared to age and sex matched controls. Those subjects with recurrent pneumonia were insensitive to capsaicin cough reflex compared to controls. We have concluded that impaired cough reflex may be related to the development of recurrent pneumonia.