Effects of 2-chloroadenosine on cortical epileptic afterdischarges in immature rats

Adenosine may represent an endogenous anticonvulsant in the brain. this study focused on the possible anticonvulsant action of an adenosine agonist,2-chloroadenosine,against cortical epileptic afterdischarges (ads) in immature rats. three age groups of rat pups with implanted electrodes were studied: 12-,18- and 25-days-old. the compound,2-chloroadenosine,was injected after the first successful stimulation at doses of 1,4 or 10 mg/kg intraperitoneally,and stimulation at the same intensity was repeated three more times. movements directly elicited by stimulation,as well as clonic seizures accompanying electroencephalography (eeg) ads,were markedly suppressed in only the 18-day-old animals. the effects in the 12- and especially the 25-day-old rats were moderate. the duration of the ads decreased in all three age groups with 2-chloroadenosine treatment,and the shortest ad duration was seen in the treated,12-day-old rats. the ad suppression also lasted longer in this age group than it did in the older animals. after a brief suppression of the second ad,the treated,25-day-old group exhibited a significant ad rebound during the third and fourth stimula-tions. taken together,our data show that 2-chloroadenosine exhibits an anticonvulsant effect that is dose-and age-dependent. © 2010 by institute of pharmacology polish academy of sciences.