title: Antiepileptic effects of a calcium antagonist (nimodipine) on cefazolin-induced epileptogenic foci in rabbits.
abstract: The epileptogenic properties of cefazolin (CFZ) were utilized to induce an electrophysiological pattern of epilepsy in the rabbit. CFZ, cortically applied in different concentrations (2 or 4%), produced epileptic activity in a degree proportional to the concentration of the substance. In this experimental epilepsy model, we evaluated the effects of increasing doses (0.025, 0.05, and 0.1 mg/kg i.v.) of the calcium antagonist nimodipine (Bay e 9736). In the evaluation of nimodipine effects, the spike-and-wave burst frequency per minute was taken into account. These data were compared with those of placebo-treated (Bay e 9736 control test) control groups and statistically evaluated by two-tailed t test. In 2% CFZ-induced epilepsy, nimodipine at the 0.025- and 0.05-mg/kg doses did not produce significant changes in the EEG pattern. A statistically significant reduction (p less than 0.001) in epileptic activity was observed at the 0.1-mg/kg nimodipine dose. This reduction was seen first in the contralateral focus leads and persisted for the entire time of observation. In the more intense epileptic form (4% CFZ), nimodipine at the doses employed did not induce noteworthy EEG modifications. These data indicate that nimodipine exerts an antiepileptic effect. The possible mechanisms involved in this activity of a calcium antagonist are discussed.
mesh_terms: D000818:Animals; D000927:Anticonvulsants / Q000627:therapeutic use*; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D002437:Cefazolin; D004569:Electroencephalography; D004828:Epilepsies, Partial / Q000139:chemically induced; D004827:Epilepsy / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D008297:Male; D009553:Nimodipine / Q000627:therapeutic use*; D011817:Rabbits
chemical_list: D000927:Anticonvulsants; D002121:Calcium Channel Blockers; D009553:Nimodipine; D002437:Cefazolin