Figure 5

Inhibitory Effects of NE are mediated by β2-ARs. Microglia were incubated with LPS (1 ng/ml) alone or with NE (1 μM), and in the presence of (A) the α-AR antagonist phenoxybenzamine (PB, 10 μM) or the indicated amount of β-AR antagonist propanolol (Prop); or (B) indicated concentrations of the selective β2-AR antagonist ICI 118,551. Nitrite levels were measured after 24 hr. ***, P < 0.001 versus LPS alone; §§§ and §, P < 0.001 and 0.05 versus LPS plus NE.