Effects of the 5-HT3 receptor agonist 1-(m-chlorophenyl)-biguanide in the rat kindling model of epilepsy.

This study assessed the action of the serotonin3 (5-HT3) receptor agonist, 1-(m-chlorophenyl)-biguanide (m-CPBG), against both kindled seizures and kindling development from the rat amygdala (AM). The intracerebroventricular (i.c.v.) administration of 40 microg m-CPBG significantly increased the duration of afterdischarge and bilateral forelimb clonus of generalized kindled seizures. In addition, daily i.c.v. treatment with m-CPBG at the same dose prior to each electrical stimulation to the AM significantly facilitated behavioral and electrographic seizure development and reduced the number of stimulations needed to elicit generalized seizures. The present results indicate that m-CPBG increases the duration of fully kindled seizures and facilitates the developmental seizure process, suggesting an excitatory role of 5-HT3 receptors in the kindling model of epilepsy.