The Antiepileptic Effect of Carbamazepine During Estrous Cycle in Pentylenetetrazol-Induced Seizures in Rat

Abstract

Catamenial epilepsy is a special kind of epilepsy related to estrous cycle which estrogen and progesterone play great roles on its outbreak. Carbamazepine (CBZ) is an old antiepileptic drug which stimulates hepatic metabolizing enzymes, which can affect steroid hormone concentration. This study was planned to survey antiepileptic effect of CBZ on Pentylenetetrazol (PTZ) induced seizures during different phases of estrous cycle in rat. Seventy-two adult Wistar rats in three groups (control 20 and 30 mg/kg of CBZ) each with four subgroups (proestrus, estrus, metestrus and diestrus) were used (n = 6). Puberty was decided by vaginal smears and animal with two normal cycles were chosen. Twenty and 30 mg/kg of CBZ were injected intraperitoneally (i.p) in the treatment groups followed by i.p injection of 80 mg/kg PTZ in the treatment and control groups. Animals were observed for 30 min and initiation time of myoclonic seizures (ITMS), initiation time of tonic–clonic seizures (ITTS), seizures duration (SD) and mortality rate (MR) were registered. Data were analyzed by one way analysis of variances and Tukey–Kramer multiple comparison post hoc tests (P ≤ 0.05). According to the results, CBZ significantly increased ITMS and ITTS while decreased SD and MR compared to control group (P ≤ 0.05). Also, antiepileptic effect of CBZ was significantly more prominent during luteal phase than follicular phase (P ≤ 0.05). These findings suggest that CBZ has antiepileptic role which is more prominent during luteal phase than follicular phase.