A striatal serotonergic involvement in the behavioural effects of anticholinesterase organophosphates

Acute administration of the anticholinesterase agents diisopropylfluorophosphate, soman, sarin and tabun to rats in sub-convulsive doses produced tremors and hind-limb abduction. The ratios of the levels of 5-HIAA to 5-HT in the striatum showed a consistent tendency to be increased, suggesting an increase in 5-HT turnover. Both the behavioural and the biochemical changes were antagonized by atropine. The possible involvement of a cholinergic-serotonergic interaction in these tremors and hind-limb abduction is discussed.