Abstract
Our data give evidence that CXCR3 ligands exhibit pronociceptive properties and play an important role in the initiation, development and maintenance of neuropathic pain. Moreover, intrathecal administration of each CXCR3 ligand induced hypersensitivity reactions in naive mice and of its neutralizing antibodies diminished neuropathic pain syndrome in CCI-exposed mice. Furthermore, our results indicate that selective CXCR3 antagonist (±)-NBI-74330 reduced the neuropathic pain-related behaviour and also enhanced morphine analgesic potency in CCI-exposed rats. Interestingly, our data show that (±)-NBI-74330 administration diminished the spinal IBA1 and, in parallel, downregulated CXCL4, CXCL9 and CXCL10. In addition, CXCR3 antagonist increased the spinal GFAP, what correlates with upregulation of CXCR3 and CXCL11. Moreover, in DRG (±)-NBI-74330 did not change IBA1 and GFAP positive cells activation, however downregulated also CXCL9. CXCR3 and CXCL10 were co-localized predominantly with neuronal marker in the spinal cord. Summing up, chronic (±)-NBI-74330 intrathecal injection promotes beneficial analgesic effects in rat neuropathic pain model, as described in details in "Pharmacological blockade of CXCR3 by (±)-NBI-74330 reduces neuropathic pain and enhances opioid effectiveness - evidence from in vivo and in vitro studies" (Piotrowska et al., 2018).