Functional depletion of capsaicin-sensitive primary afferent fibers attenuates rat pain-related behaviors and paw edema induced by the venom of scorpion Buthus martensi Karch.
The role of capsaicin-sensitive primary afferent fibers in rat pain-related behaviors and paw edema induced by scorpion Buthus martensi Karch (BmK) venom was investigated in this study. It was found that functional depletion of capsaicin-sensitive primary afferent fibers with a single systemic injection of resiniferatoxin (RTX) dramatically decreased spontaneous nociceptive behaviors, prevented the development of primary mechanical and thermal hyperalgesia as well as mirror-image mechanical hyperalgesia. RTX treatment significantly attenuated BmK venom-induced c-Fos expression in all laminaes of bilateral L4-L5 lumbar spinal cord, especially in superficial laminaes. Moreover, RTX treatment markedly reduced the early paw edema induced by BmK venom. Thus, the results indicate that capsaicin-sensitive primary afferent fibers play a critical role in various pain-related behaviors and paw edema induced by BmK venom in rats.
Bai
Zhan-Tao
ZT
College of Life Sciences, Yanan University, Yanan 716000, PR China.
Liu
Tong
T
Pang
Xue-Yan
XY
Jiang
Feng
F
Cheng
Ming
M
Ji
Yong-Hua
YH
D000818:Animals; D002211:Capsaicin / Q000378:metabolism*; D004224:Diterpenes / Q000494:pharmacology; D004487:Edema / Q000503:physiopathology*; D006614:Hindlimb; D006930:Hyperalgesia / Q000503:physiopathology; D007150:Immunohistochemistry; D009475:Neurons, Afferent / Q000187:drug effects / Q000502:physiology*; D009619:Nociceptors / Q000502:physiology*; D010146:Pain / Q000503:physiopathology*; D017288:Pain Threshold; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012604:Scorpion Venoms / Q000009:adverse effects*; D013116:Spinal Cord / Q000378:metabolism
D004224:Diterpenes; D016760:Proto-Oncogene Proteins c-fos; D012604:Scorpion Venoms; C024353:resiniferatoxin; D002211:Capsaicin