Phosphorylation at Ser 727 Increases STAT3 Interaction with PKC Regulating Neuron-Glia Crosstalk via IL-6-Mediated Hyperalgesia In Vivo and In Vitro.

Methods: A rat hyperalgesia model was induced using an intraplantar injection of Freund's complete adjuvant (FCA) or an intrathecal injection of IL-6. Mechanical allodynia was evaluated using von Frey filament tests after intrathecal injections of T-5224 (c-Fos/AP-1 inhibitor), minocycline (Mino, a specific microglia inhibitor), L-2-aminoadipic acid (LAA, an astroglial toxin), PKC inhibitor peptide, APTSTAT3-9R (STAT3 inhibitor), or anti-IL-6 antibody. The c-Fos, GFAP, Iba-1, PKC, STAT3, pSTAT3 and pSTAT3, and IL-6 expression at the spinal cord level was assessed by Western blot analysis.