Protective effect of clonidine against soman intoxication

Clonidine prophylactic action against soman intoxication was investigated. The results showed that clonidine itself inhibited the brain cholinesterase(ChE) activity only at high concentrations(1-10 mmol·L -1 ) in vitro, and didn′t inhibited the brain and blood ChE obviously at 1 mg·kg -1 ip in mice. The pretreatment of clonidine could not affect the brain and blood ChE activity of soman intoxicated mice significantly, but it could significantly suppressed the incidence of soman induced seizure and death. Yohimbine expressed obviously antagonistic action against the protective effect of clonidine in soman intoxication. It suggests that the α 2 adrenergic receptor activation mediate the protective action of clonidine against soman intoxication.