Diagram of potential/known Mn sites of action in microglial intracellular signaling following activation with LPS. Small arrows indicate known intracellular signaling pathways while larger arrows indicate possible sites of interaction between signaling molecules and Mn. Large arrows with a ‘?’ denote potential sites of action for Mn-enhanced p38 acitivity. Abbreviations: LPS (Lipopolysaccharide), LBP (LPS Binding Protein), TLR4 (Toll Like Receptor 4), MKK3/6 (Mitogen Activated Protein Kinase Kinase) p38 (p38 Mitogen Activated Protein Kinase), p38-p (phosphorylated p38), ERK (Extracellular Signal-Regulated Kinase), MAPKAP-k2 (MAPK Phosphatase), IkB (Inhibitor of NF-kB), NF-kB (Nuclear Factor kappa B), TBP (TATA-Binding Protein), TATA (TATA Box).