Anticonvulsive effect of vitamin C on pentylenetetrazol-induced seizures in immature rats

Abstract

Vitamin C helps to prevent brain oxidative stress and participate in the synthesis of progesterone. It also possesses a progesterone-like effect and acts synergistically with progesterone on the brain. Progesterone and its metabolites, but also vitamin C have been associated with anticonvulsant effects. We evaluated the progesterone concentration 30 min and 24 h after the last administration of vitamin C (500 mg/kg, i.p. for five days). We also evaluated how vitamin C altered pentylenetetrazol (PTZ)-induced seizures by measuring the onset latency of seizures, percentage of incidence and mortality as well as amino acid levels after seizures. Vitamin C treatment alone increased basal progesterone concentrations to 531% after 30 min compared to 253% after 24 h. Furthermore, vitamin C significantly increased the latency to the first myoclonic, clonic and tonic seizure induced by PTZ (80 mg/kg, i.p.) and decreased the percentage of incidence of clonic and tonic seizures as well as the mortality rate. Changes in tissue concentration of amino acids were primarily observed at 24 h after vitamin C treatment. Our results suggest that vitamin C together with progesterone and/or its metabolites are involved in the protection against PTZ-induced seizures in immature rats.