Abstract

Bitter orange leaf (Citrus aurantium, CA) has anticonvulsant and anxiolytic properties. We examined the effect of a hydroethanolic CA extract (CAe) on seizure behavior. Adult Zebrafish (Danio rerio) were pre-incubated with different CAe concentrations, while untreated fish served as controls. The convulsant activity was assessed by exposing fish to pentylenetetrazole (3 mg/mL) and recording the seizure latency. Proconvulsant effects are observed at low CAe concentrations (0.005-0.063 mg/mL), followed by an apparent plateau, and at concentrations above 0.175 mg/mL, anticonvulsant effects. The proconvulsant effects might be due to the interaction of glutamate receptors (GluR) because CA increases [3H]glutamate binding at low concentrations (0.001-0.01mg/mL), interacting with NMDA and mGluR-II receptors. An aqueous extract, CAa, has similar anticonvulsant properties to those of the leaf infusion. Understanding the mechanisms underlying the proconvulsant effects of low CAe doses could identify strategies to reduce or eliminate them, ultimately enhancing its therapeutic potential.

Keywords

Citrus aurantium, pentylenetetrazole, zebrafish, proconvulsant, anticonvulsant