Expression of ORL1 mRNA in some brain nuclei in neuropathic pain rats.
The present study was designed to investigate changes of opioid receptor like 1 receptor (ORL(1), NOP) mRNA expression in some pain-related brain nuclei of neuropathic pain rats using in situ hybridization technique. Nociceptin/orphanin FQ (N/OFQ), the endogenous ligand of ORL(1), plays an important role in neuropathic pain through its receptor. There are ORL(1) mRNA expression in the nucleus of raphe magnus (NRM), ventrolateral periaqueductal gray (vlPAG) and dorsal raphe nucleus (DRN) of rat mesencephalon. In the sciatic nerve chronic constriction injury (CCI)-induced neuropathic pain model, a significant increase of ORL(1) mRNA expression was observed in these three regions on the 7th day after operation, and the changes lasted for 2 weeks. The result indicated that ORL(1) synthesis was increased in NRM, vlPAG and DRN of neuropathic pain rats, suggesting that ORL(1) was involved in nociceptive transmission of neuropathic pain.
Ma
Fei
F
Department of Integrative Medicine and Neurobiology, Institute of Acupuncture Research, Shanghai Medical College of Fudan University, P.O. Box 291, 138 Yi Xue Yuan Road, Shanghai 200032, China.
Xie
Hong
H
Dong
Zhi-Qiang
ZQ
Wang
Yan-Qing
YQ
Wu
Gen-Cheng
GC
D000818:Animals; D015870:Gene Expression; D017403:In Situ Hybridization; D008297:Male; D010487:Periaqueductal Gray / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D011903:Raphe Nuclei / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011957:Receptors, Opioid / Q000235:genetics*; D012585:Sciatica / Q000503:physiopathology*; D000094942:Nociceptin Receptor
D012333:RNA, Messenger; D011957:Receptors, Opioid; D000094942:Nociceptin Receptor; C000722285:Oprl1 protein, rat