Abstract:Objective: To study the effects of cholinergic neurons and GABAergic neurons in the medial septum (MS) in chronic neuropathic pain of rats with spinal nerve injury (SNI). Methods: First, SNI rats were divided into two groups: the SAP-lesion group (SNI rats with cholinergic neurons specifically lesioned by 192 IgG-saporin), and the SAP-control group (SNI rats with sham lesion). The mechanical allodynia was examined with von Frey hair, and the emotion was evaluated by conditioned place aversion (CPA). Similarly, GABAergic neurons in the medial septum were lesioned by kainic acid (KA), and the SNI rats were also divided into two groups: SNI with KA lesion (the KA-lesion group) and SNI with sham lesion (the KA-control group). The mechanical allodynia was also examined with von Frey hair. Results: Specific lesion of either cholinergic neurons or GABAergic neurons in the medial septum significantly relieved neuropathic pain and alleviated the aversion in chronic pain rats after SNI. Conclusion: Both cholinergic neurons and GABAergic neurons in the medial septum are involved in neuropathic pain.