Adrenoceptors in lung tissue: characterization, modulation and relations with pulmonary function

Adrenoceptor (sub)populations (alpha 1, beta and beta 1/beta 2 ratio) in human lung tissue were characterized by means of radioligand binding assays. Lung tissue specimens for these assays were obtained at thoracotomy from normal individuals and COLD patients. The patients were not receiving therapy known to influence adrenoceptor characteristics. In COLD patients, the number of alpha 1-adrenoceptors appeared to be markedly enhanced while the relative amount of beta 2-adrenoceptors was decreased. Furthermore, some adrenoceptors seemed to be correlated to pulmonary function both in the normal individuals and COLD patients. In-vitro modulation with disodium cromoglycate and ketotifen revealed therapeutic possibilities for these substances based on other pharmacological mechanisms than hitherto assumed.