Anti-hypersensitivity effects of Shu-jing-huo-xue-tang, a Chinese herbal medicine, in CCI-neuropathic rats.
OBJECTIVE
Shu-jing-huo-xue-tang (SJHXT) (Japanese name: Sokei-kakketu-to), a traditional Chinese herbal medicine composed of 17 crude drugs, has been prescribed over hundreds of years for treatment of chronic pain syndromes. We evaluated if oral SJHXT could suppress neuropathic pain behaviors in rats with chronic constriction injury (CCI) of the sciatic nerve.


METHODS
(1) Rats received repeated oral SJHXT 0.5 or 1.0 g/kg once daily for 14 days starting 24 h after CCI surgery, while neuropathic manifestations were evaluated until day 20 post-CCI. (2) Other groups of rats received single oral SJHXT 1.0 g/kg on day 14 post-CCI. (3) Additional groups of rats received oral SJHXT 1.0 g/kg on day 14 post-CCI, concomitantly with intraperitoneal yohimbine 1 mg/kg or methysergide 5 mg/kg. Neuropathic manifestations, including mechanical allodynia and thermal hyperalgesia, were evaluated with paw withdrawal responses to increasing mechanical pressure and radiant heat, respectively.


RESULTS
Mechanical allodynia and thermal hyperalgesia developed by day 14 post-CCI. Repeated oral SJHXT for 14 days produced anti-allodynic and anti-hyperalgesic effects that outlasted the period of drug administration. Single oral SJHXT on day 14 also produced significant anti-allodynic and anti-hyperalgesic effects, which were inhibited by yohimbine, an alpha-2 adrenoceptor antagonist, but not by methysergide, a serotonin receptor antagonist.


CONCLUSIONS
Oral SJHXT produced anti-hypersensitivity effects by actions on alpha-2 adrenoreceptors in CCI-neuropathic rats, and chronic oral administration of SJHXT could produce the long-lasting anti-hypersensitivity effects.
Shu
Haihua
H
Department of Anesthesiology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.
Arita
Hideko
H
Hayashida
Masakazu
M
Zhang
Liang
L
An
Ke
K
Huang
Wenqi
W
Hanaoka
Kazuo
K
D058669:Adrenergic alpha-2 Receptor Antagonists / Q000494:pharmacology; D000700:Analgesics / Q000494:pharmacology / Q000627:therapeutic use*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D003250:Constriction; D004365:Drugs, Chinese Herbal / Q000494:pharmacology / Q000627:therapeutic use*; D006358:Hot Temperature; D006930:Hyperalgesia / Q000188:drug therapy*; D019684:Magnoliopsida; D008297:Male; D008784:Methysergide / Q000494:pharmacology; D009437:Neuralgia / Q000188:drug therapy*; D008517:Phytotherapy; D011312:Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000293:injuries; D020426:Sciatic Neuropathy / Q000188:drug therapy*; D012702:Serotonin Antagonists / Q000494:pharmacology; D015016:Yohimbine / Q000494:pharmacology
D058669:Adrenergic alpha-2 Receptor Antagonists; D000700:Analgesics; D004365:Drugs, Chinese Herbal; D012702:Serotonin Antagonists; D015016:Yohimbine; D008784:Methysergide