6533b823fe1ef96bd127ec12

RESEARCH PRODUCT

Control of the production of oxygen intermediates of human polymorphonuclear leukocytes and monocytes by beta-adrenergic receptors.

subject

description

The control by beta-adrenergic receptors of the production of oxygen radicals by zymosan-stimulated human polymorphonuclear leukocytes (PMN) and monocytes (M phi) was studied in vitro by means of chemiluminescence. In addition we asked whether PMN and M phi exhibit differential sensitivity to beta-adrenergic stimulation. For beta-adrenergic stimulation we applied fenoterol ranging from 10(-5) to 10(-9) M x 2.7. We found a dose-dependent suppression of the production of oxygen radicals, the ID50 being approximately 10(-6) M both for PMN and M phi. By assessment of lactic dehydrogenase release a cytotoxic effect of the drug could be ruled out. When incubated together with the beta-adrenergic antagonist propranolol at 10(-6) and 10(-7) M the suppression effect of fenoterol could be reversed in dose-dependency. Preincubation with fenoterol revealed that the inhibitory action on M phi persisted, in contrast, no such suppression could be verified with PMN. Our findings indicate the control of the production of oxygen intermediates of human PMN and M phi by beta-adrenergic stimulation. Furthermore, selective functional modulation of resting PMN and M phi by beta-adrenoceptors is suggested. These effects may be of importance in vivo, in particular since fenoterol was applied in pharmacological doses.