Fos expression in rat spinal cord induced by peripheral injection of BmK I, an alpha-like scorpion neurotoxin.
In this paper, the central neuronal activities elicited by BmK I, a specific voltage-gated Na+ channel modulator, were examined by monitoring the c-Fos expression pattern of rat spinal cord. c-Fos protein in laminae I-II, V-VI, and VII-X could be detected at 0.5 h, increased steadily at 1 h, reached a peak at 2 h, and then decreased rapidly from 4 to 24 h after Bmk I was subcutaneously injected into the rat hind paw. However, c-Fos expression in laminae III-IV was activated to a peak at 0.5 h and then declined gradually from 0.5 to 24 h. Furthermore, c-Fos expression could be induced by BmK I in a dose-dependent manner. In addition, the increase of c-Fos expression in laminae I-II, V-VI, and VII-X induced by BmK I, and not in laminae III-IV, could be partially inhibited by systemic morphine in a dose-dependent manner. The results suggested that peripheral administration of BmK I could evoke a profound change of spinal neuronal activities manifested as specific patterns of c-Fos expression, which may be partially attributed to the selective modulation of BmK I on voltage-gated Na+ channels located in peripheral nociceptors.
Bai
Zhan-Tao
ZT
The Key Laboratory of Neuroscience, Institute of Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
Zhang
Xu-Ying
XY
Ji
Yong-Hua
YH
D000701:Analgesics, Opioid / Q000494:pharmacology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D002452:Cell Count; D004305:Dose-Response Relationship, Drug; D015870:Gene Expression / Q000187:drug effects*; D016762:Genes, fos / Q000187:drug effects*; D007150:Immunohistochemistry; D008297:Male; D009020:Morphine / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D009498:Neurotoxins / Q000008:administration & dosage / Q000633:toxicity*; D010146:Pain / Q000139:chemically induced / Q000523:psychology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012604:Scorpion Venoms / Q000008:administration & dosage / Q000633:toxicity*; D013116:Spinal Cord / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*
D000701:Analgesics, Opioid; D009498:Neurotoxins; D012604:Scorpion Venoms; C105338:makatoxin I; D009020:Morphine