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.

Abstract

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.

• Authors: Zhan-Tao Bai, Tong Liu, Xue-Yan Pang, Feng Jiang, Ming Cheng, Yong-Hua Ji
• Journal: Neuroscience research (Neurosci Res) Vol. 62 Issue 2 Pg. 78-85 (Oct 2008) ISSN: 0168-0102 [Print] Ireland
• PMID: 18619501 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Diterpenes
• Proto-Oncogene Proteins c-fos
• Scorpion Venoms
• resiniferatoxin
• Capsaicin

Topics

• Animals
• Capsaicin (metabolism)
• Diterpenes (pharmacology)
• Edema (physiopathology)
• Hindlimb
• Hyperalgesia (physiopathology)
• Immunohistochemistry
• Neurons, Afferent (drug effects, physiology)
• Nociceptors (physiology)
• Pain (physiopathology)
• Pain Threshold
• Proto-Oncogene Proteins c-fos (biosynthesis)
• Rats
• Rats, Sprague-Dawley
• Scorpion Venoms (adverse effects)
• Spinal Cord (metabolism)