Adenosine antagonists. Lack of effect on the inhibition of kindled seizures in rats by carbamazepine.

This study investigates the ability of adenosine antagonists to reverse the anticonvulsant effects of carbamazepine on amygdala-kindled seizures in order to elucidate the possible physiological relevance of the potent effects of carbamazepine on adenosine receptors. At large but subconvulsant doses, neither caffeine nor theophylline altered the anticonvulsant potency of carbamazepine, even though caffeine by itself significantly increased the duration of the kindled afterdischarge. The adenosine agonist cyclohexyladenosine (CHA), administered intraperitoneally at a dose that produced sedation, had no effect on the kindled seizures. Although carbamazepine potently displaces the binding of several adenosine ligands in vitro, the present data do not suggest that the anticonvulsant effects of carbamazepine on amygdalakindled seizures are mediated by an adenosine agonist-like action.