To determine the relationship between airway and coronary artery spasmogenesity in patients with vasospastic angina pectoris (VSAP), we measured the bronchial responsiveness to inhaled methacholine in 21 VSAP patients (V-group) and compared it to that of 17 chest pain syndrome patients with normal coronary (N-group). In the V-group, logarithmic values of the minimum cumulative dose required to decrease respiratory conductance from the baseline (Log Dmin) was significantly lower than that in N-group (0.47 +/- 0.60 log units vs. 0.98 +/- 0.60 log units respectively, p < 0.05). Log Dmin was significantly correlated with the dose of acetylcholine which induced a greater than 90% stenosis of the coronary artery (r = 0.383, p < 0.05). We concluded that both the coronary artery and the airway show hyperresponsiveness to cholinergic agonists in patients with VSAP.