Pain
-
Oxytocin (OXT) is a neuropeptide hormone synthesized and secreted by hypothalamic neurons and has been reported to play a significant role in pain modulation. However, the mechanisms underlying OXT's antinociceptive effect on neuropathic pain are not fully understood. In this study, we examined the peripheral effect of OXT on mechanical hypersensitivity induced by partial ligation of the infraorbital nerve (PNL) in rats. ⋯ Furthermore, intra-TG administration of a selective V1A-R antagonist reversed the OXT-induced alleviation of mechanical hypersensitivity, and coapplication of the antagonist opposed OXT's effects on the resting membrane potential, rheobase, and K current. These findings suggest that OXT is effective at suppressing TG neuronal hyperexcitability after nerve injury, likely by modulation of voltage-gated K channels through V1A-R. This signaling mechanism represents a potential therapeutic target for the treatment of orofacial neuropathic pain.