Pathophysiological Aspects of Temporal Lobe Epilepsy and the Role of P2X Receptors

In the central nervous system (CNS), ATP is released from vesicles at nerve terminals in a frequency- dependent manner and can activate P2 receptors widely expressed and distributed in the CNS. In addition to interacting with P2 receptors, ATP can be rapidly hydrolyzed to adenosine to activate P1 receptors modulating neuronal transmission. Thus, complex synaptic interactions in the CNS are modulated by P2 and P1 receptors. This review focuses on the role of P2X receptors in temporal lobe epilepsy. P2X receptors are cationic-selective channels gated by extracellular ATP. Seven subunits (P2X1-7) are expressed throughout the central nervous system and are involved with modulatory mechanisms of neurotransmitter release, hyperexcitability, intracellular calcium influx, cell-cell communication, neuroprotection, and cell death. This review discusses the current data regarding the involvement of P2 receptors in the pathophysiology of tempo- ral lobe epilepsy (TLE).