Zhao Yu-Long, Yi Hui-Yuan, Baba Sani Sa'idu, Guo Yi-Xiao, Yuan Xiao-Cui, Hou Xue-Mei, Liang Ling-Li, Huo Fu-Quan
Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China.
Institute of Neuroscience, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi, China.
Mol Neurobiol. 2025 Jan;62(1):1136-1150. doi: 10.1007/s12035-024-04314-1. Epub 2024 Jul 4.
The comorbidity of anxiety and depression frequently occurs in patients with neuropathic pain. The ventrolateral orbital cortex (VLO) plays a critical role in mediating neuropathic pain and anxiodepression in rodents. Previous studies suggested that 5-HT receptors in the VLO are involved in neuropathic pain. Strong evidence supports a close link between 5-HT receptors and affective disorders such as depression and anxiety disorders. However, it remains unclear whether the 5-HT receptors in the VLO are involved in neuropathic pain-induced anxiodepression. Using a rat neuropathic pain model of spared nerve injury (SNI), we demonstrated that rats exhibited significant anxiodepression-like behaviors and the expression of VLO 5-HT receptors obviously decreased four weeks after SNI surgery. Microinjection of the 5-HT receptor agonist EMD-386088 into the VLO or overexpression of VLO 5-HT receptors alleviated anxiodepression-like behaviors. These effects were blocked by pre-microinjection of a selective 5-HT receptor antagonist (SB-258585) or inhibitors of AC (SQ-22536), PKA (H89), and MEK1/2 (U0126) respectively. Meanwhile, the expression of p-ERK, p-CREB, and BDNF in the VLO decreased four weeks after SNI surgery. Furthermore, administration of EMD-386088 upregulated the expression of BDNF, p-ERK, and p-CREB in the VLO of SNI rats, which were reversed by pre-injection of SB-258585. These findings suggest that activating 5-HT receptors in the VLO has anti-anxiodepressive effects in rats with neuropathic pain via activating AC-cAMP-PKA-MERK-CREB-BDNF signaling pathway. Accordingly, 5-HT receptor in the VLO could be a potential target for the treatment of the comorbidity of neuropathic pain and anxiodepression.
Psychopharmacology (Berl). 2020-5-28
Front Mol Neurosci. 2023-2-20