Objective: To investigate the role of substance P (SP) in chronic obstructive pulmonary disease (COPD) or asthma.
Method: Plasma and sputum samples were obtained from 26 COPD patients and 20 asthmatic patients as well as 12 healthy subjects for measurement of SP content.
Results: Patients with COPD had significantly higher levels of SP in the plasma (7.9+/-2.6 pmol/L) and sputum (53.8+/-12.5 pmol/L) than the healthy subjects (3.6+/-1.7 pmol/L and 6.2+/-2.3 pmol/L, respectively, P<0.01). The asthmatic patients also had significantly higher SP levels (8.3+/-3.1 pmol/L and 46.9+/-10.2 pmol/L, respectively) than the healthy subjects, but there was no significant difference between COPD and asthmatic patients (P>0.05).
Conclusion: SP may be involved in the airway inflammation process in COPD and asthma.