in order to assess the involvement of alpha-2 adrenergic receptors in nociception , the in vitro potencies of seven alpha-2 adrenergic agonists ( clonidine , guanabenz , guanfacine , bht-920 , ici 106270 , xylazine and lofexidine ) were compared with their ability to prevent the writhing response elicited by i.p . administration of phenyl-p-guinone .
C1373110
alpha-2 adrenergic agonists
C0018312
guanabenz