Characterization of the purinergic system in the temporal lobe epilepsy: approach in the experimental model of pilocarpine

Abstract

Pilocarpine is a cholinergic agonist which, when inject on high doses (i.p.) in rats, reproduces the main characteristics of Human Temporal Lobe Epilepsy (TLE). The animal exhibits different patterns of behavior, including status epilepticus (acute phase), behavioral normalization (latent phase) and spontaneous and recurrent seizures (chronic phase). The objectives of this study are to analyze by means of microdyalysis and HPLC, the concentration of ATP and its metabolites ADP, AMP and adenosine in the hippocampus of rats during the acute and chronic phases of pilocarpine model. The western blotting method will be applied to study the purinoceptors P2X2,4,7 in the hippocampus of these animals. By microdyalysis procedure we will determine the concentration of purines released during status epilepticus (SE) in samples taken in different times following treatments: Basal, methylscopolamine (used in order to minimize the peripheral effects of pilocarpine) and 1H, 2H, 3H and 4H after status epilepticus. The chronic animals will be studied during the interictal period. The samples will be analyzed by a fluorescence detector coupled to HPLC. Animals from three different experimental groups (G12H, GLat, GCro) and their respective controls will be used to study purinergic receptors by western blotting. (AU)