Effects of alpha1- and alpha2-adrenoreceptor antagonists on cold allodynia in a rat tail model of neuropathic pain.
Systemic administrations (0.1, 0.5, and 2 mg/kg) of alpha1-adrenoreceptor (AR) antagonist prazosin dose-dependently attenuated cold allodynia in a rat tail model of neuropathic pain, whereas alpha2-AR antagonist yohimbine exacerbated it. These results suggest that the functions of alpha1- and alpha2-AR in this model are excitatory and inhibitory, respectively, consistent with their general properties. It is also proposed that cold allodynia can be reversed by alpha1-AR antagonist and exacerbated by alpha2-AR antagonist.
Kim
Sun Kwang
SK
Department of East-West Medicine, Graduate School, Kyung-Hee University, Seoul, South Korea.
Min
Byung-Il
BI
Kim
Ji Hoon
JH
Hwang
Byung Gil
BG
Yoo
Gi Yong
GY
Park
Dong Suk
DS
Na
Heung Sik
HS
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D003080:Cold Temperature; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D006930:Hyperalgesia / Q000503:physiopathology; D008297:Male; D009619:Nociceptors / Q000187:drug effects; D017288:Pain Threshold / Q000187:drug effects*; D011224:Prazosin / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013127:Spinal Nerves / Q000187:drug effects* / Q000293:injuries / Q000503:physiopathology; D013623:Tail / Q000294:innervation; D015016:Yohimbine / Q000494:pharmacology*
D000317:Adrenergic alpha-Antagonists; D000319:Adrenergic beta-Antagonists; D015016:Yohimbine; D011224:Prazosin