Here, the role of vlPAG OX1Rs and their interaction with cannabinoid 1 (CB1) receptor was evaluated in anxiety-like behavior following capsaicin-induced dental pulp pain.
In addition, LTD was dependent on the NMDA receptor, as the NMDA receptor antagonist D-AP5 blocked the maintenance of LTD. Our study suggests that orexins, via activation of both OX1 and OX2, play a significant role in the expression of NMDA-dependent LTD, thereby contributing to the spinal modulation of pain transmission.
The roles of orexinergic system (orexin-A, orexin-B) and their receptors (orexin receptor type-1, orexin receptor type-2) in various physiological processes such as arousal, reward seeking behavior, energy homeostasis, sensory modulation, stress processing, cognition, endocrine functions, visceral functions and pain modulation have been established.