The effects of cAMP-PKA activation/inhibition upon macrophage TLR4 activation in vitro. BMM were stimulated with LPS in the absence or presence of Forskolin (PKA activator), H-89 (PKA inhibitor), or DMSO (control). The expression of (a) TNF-α, IL-6, IL-12p40, and (b) IL-10 are shown. (**p<0.01, ***p<0.05, n=6/group).