PROFILE OF CHICKEN MACROPHAGE FUNCTIONS AFTER EXPOSURE TO CATECHOLAMINES IN-VITRO

The effects of catecholamines (CA) on various chicken macrophage funct ions were examined. Macrophage monolayers were exposed to .01, .1, .25 , 1, 2, and 5 mu g/mL of dopamine (DA), norepinephrine (NE) and epinep hrine (E) for 1 hr. All CA were toxic for macrophages at 1 - 5 mu g do se range resulting in 25-50% cell death. All CA at the .1 and .25 mu g /mL level increased E. coli and sheep red blood cells (SRBC) phagocyto sis by macrophages. The percentage of Fc-receptor positive macrophages increased after CA exposure. Prolonged exposure of macrophages (3 hr) reduced SRBC phagocytosis by DA-treated but not in NE- and. E-treated macrophages. However, after 1 hr exposure and 3 hr recovery period, C A-induced changes were reversed in all but DA-treated cultures. Apomor phine and metoclopromide blocked DA whereas propranolol blocked NE and E effects suggesting specificity of the observed effects via catechol aminergic receptors on chicken macrophages. Dopamine and NE (.25 mu g/ mL) did not affect but E exposure enhanced LPS-induced tumoricidal fac tor production. These findings suggest that CA modulate chicken macrop hage effector functions.