Receptors like 5HT3, GABAA, glycine, and nicotinic acetylcholine (nACh) belong to a superfamily of ligand gated ion channels and subunits of these receptors exhibit extensive amino acid sequence homology receptors. May be due to these facts drugs acting on the 5HT3 receptor can also act on other. For example, some 5HT3 receptor antagonists can act on the GABAA receptor complex in addition to their effects on 5HT3 receptors.
This particular study was conducted to evaluate the anticonvulsant action of Ondansetron and compare it with Phenytoin sodium. 30 albino rats of male sex weighing 150-200g each are selected and randomly divided into 5 equal groups. Maximal Electroshock (MES) seizures were induced in albino rats via transauricular electrodes (150mA, 0.2 seconds). Each rat were pretreated with intraperitoneal drugs i.,e, 30 minutes before MES test. The group 1 is given normal saline 1ml/kg, Group 2 is given phenytoin Sodium (25 mg/kg), group 3 ondansetron (0.5 mg/kg), group 4 ondansetron (1 mg/kg) and group 5 ondansetron (2 mg/kg). ANOVA test was used for statistical analysis of the data.
In present study only 33.33% of the rats were protected from MES induced seizures in Ondansetron 0.5 mg/kg group but protection was not comparable to standard Phenytoin sodium. Ondansetron in 1 mg and 2 mg/kg did not give any protection against MES induced seizures. Though the previously conducted studies on the antiepileptic activity of ondansetron provide sufficient evidences to support its antiepileptic activity, present study failed to reproduce similar protection in MES induced seizures.