title: Chronic propranolol treatment affects expression of adrenoceptors on peritoneal macrophages and their ability to produce hydrogen peroxide and nitric oxide.
abstract: Using both immunocytochemical and flow cytometric analyses of rat peritoneal exudate cells constitutive expression of tyrosine hydroxylase and both beta(2)- and alpha(1)- adrenoceptors on macrophages was revealed. Furthermore, according to the characteristic assemblage of tyrosine hydroxylase and adrenoceptor subtype expression different macrophage subsets were identified. In vitro treatment of macrophages with the non-selective alpha,beta-adrenoceptor agonist arterenol and/or the beta-adrenoceptor antagonist propranolol indicated that beta-adrenoceptors potentiated nitric oxide (NO) production and suggested alpha-adrenoceptor-mediated suppression of hydrogen peroxide (H(2)O(2)) production. An increase in H(2)O(2) production in the presence of the alpha(1)-adrenoceptor antagonist ebrantil provided support for this. Chronic propranolol treatment in vivo led to increased NO and H(2)O(2) production by peritoneal macrophages. Furthermore, this treatment resulted in opposing effects on the expression of beta(2)- and alpha(1)-adrenoceptors on peritoneal macrophages (a stimulatory effect on beta(2)-adrenoceptors and a suppressive effect on alpha(1)-adrenoceptors). In conclusion, a subset of resident peritoneal macrophages synthesizes catecholamines, which may exert differential effects on H(2)O(2) and NO production via distinct adrenoceptors. Finally, chronic propranolol treatment affected adrenoceptor expression on peritoneal macrophages and altered their capacity to generate NO and H(2)O(2).
authors.affiliation: Immunology Research Centre "Branislav Janković", Institute of Virology, Vaccines and Sera "Torlak", Belgrade, Serbia. miradim@sezampro.yu
authors.forename: Mirjana
authors.initials: M
authors.lastname: Dimitrijević
authors.forename: Ivan
authors.initials: I
authors.lastname: Pilipović
authors.forename: Stanislava
authors.initials: S
authors.lastname: Stanojević
authors.forename: Katarina
authors.initials: K
authors.lastname: Mitić
authors.forename: Katarina
authors.initials: K
authors.lastname: Radojević
authors.forename: Vesna
authors.initials: V
authors.lastname: Pesić
authors.forename: Gordana
authors.initials: G
authors.lastname: Leposavić
mesh_terms: D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D005434:Flow Cytometry; D006861:Hydrogen Peroxide / Q000378:metabolism*; D007150:Immunohistochemistry; D017737:Macrophages, Peritoneal / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009569:Nitric Oxide / Q000096:biosynthesis*; D011433:Propranolol / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011941:Receptors, Adrenergic / Q000187:drug effects* / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000096:biosynthesis
chemical_list: D000318:Adrenergic beta-Agonists; D011941:Receptors, Adrenergic; D009569:Nitric Oxide; D011433:Propranolol; D006861:Hydrogen Peroxide; D014446:Tyrosine 3-Monooxygenase