In DRG cells, physiological level of PGE2 inhibits LPS-stimulated TNFα via EP4 receptors.
LPS-stimulated COX-2 and TNFα are auto-inhibited by endogenous PGE2 via EP4 receptors.
DRG neurons endogenously produce COX-2-derived PGE2 to regulate TLR4 activity in glia.