With strong support from our results summarized in Scheme 1, we are proposing a hypothesis that MMP-9, p38MAPK, ERK1/2 and PI3K/Akt, not TIMP-1 and the NLRP3/Caspase-1 inflammasome complex, are involved in the analgesic effects of CORM-2 in rat neuropathic pain. Here, MMP9 is linked to neuropathic pain.