Evidence that ATP participates in the pathophysiology of pilocarpine-induced temporal lobe epilepsy: Fluorometric, immunohistochemical, and western blot studies

Abstract

Purpose: This study was performed to study the role of adenosine triphosphate (ATP) in the brain of pilocarpine-induced chronic epileptic rats. Methods: ATP-mediated changes in intracellular calcium were studied by the fura-2 method. Immunohistochemistry and Western blotting methods were used to localize and quantify P2X7 receptors in these animals. Results: The fluorometric study in chronic rats revealed a biphasic response indicating the presence of P2X7 receptors. The Western blotting study showed an increase of 80% of P2X7 expression in chronic rats compared with the control group. P2X7 immunoreactivity resembled mossy fiber sprouting at the dentate gyrus of epileptic animals. Conclusions: These results suggest that purinergic receptors may participate in the pathophysiology of temporal lobe epilepsy.