THE β‐ADRENOCEPTOR OF THE HUMAN LYMPHOCYTE AND HUMAN LUNG PARENCHYMA

Abstract
1 The response of the β-adrenoceptors of human lymphocytes to selective agonists and antagonists has been studied quantitatively by measuring changes in cyclic adenosine-3′,5′-monophosphate (cyclic AMP) levels. 2 The receptor was activated by isoprenaline and by salbutamol, and blocked by propranolol but not by practolol. A similar pattern of response was obtained with fragments of human lung tissue. 3 The mean value for pA2 for propranolol was 8.34 and for practolol was 3.95. 4 These findings indicate that the lymphocyte β-adrenoceptor is a β2-receptor and support the validity of using lymphocytes to study β-adrenoceptor function in bronchial asthma. It may also be of use in the evaluation of selective β2-blocking drugs in man.