BRONCHIAL RESPONSIVENESS AND ANGIOTENSIN-CONVERTING ENZYME GENE POLYMORPHISM IN SARCOIDOSIS PATIENTS

Background: Angiotensin-converting enzyme (ACE) inactivates bradykinin and tachykinins, which are potent bronchoconstrictors and mediators o f inflammatory reactions. It has recently been shown that an insertion (I)/deletion (D) polymorphism in the ACE gene accounts for variation in serum ACE level. We investigated bronchial responsiveness in patien ts with sarcoidosis to determine whether it might be associated with A CE gene polymorphism. Subjects: Bronchial responsiveness was assessed in 21 patients with sarcoidosis, 21 patients with asthma, and 18 healt hy control subjects, ACE polymorphism was also examined in the 21 pati ents with sarcoidosis. Methods: Bronchial responsiveness was measured by recording respiratory resistance with continuous inhalation of meth acholine from 49 to 25,000 mu g/mL in concentration, The ACE genotype was determined using the polymerase chain reaction, Results: We found a significant increase in bronchial responsiveness in sarcoidosis pati ents as compared with healthy control subjects (p<0.01), In the sarcoi dosis group, patients with the II genotype demonstrated significantly more coughing (p<0.05) and a greater bronchial responsiveness (p<0.05) than did those with DI or DD genotypes. Conclusion: Patients with sar coidosis have increased bronchial responsiveness to some extent, the d egree apparently depending on the ACE genotype.