Up-regulation of P/Q-type voltage-gated Ca2+ channel immunoreactivity within parvalbumin positive neurons in the rat hippocampus following status epilepticus

To identify the roles of VGCC subtypes in damages/impairs of inhibitory transmission during epileptogenesis, we investigated temporal- and spatial-specific alterations in voltage-gated Ca2+ channel (VGCC) immunoreactivities within parvalbumin (PV, a Ca2+ binding protein) positive neurons in the rat hippocampus following status epilepticus (SE). Compared to controls, only P/Q-type (α1A) VGCC immunoreactivity was enhanced in PV positive neurons at the early point following SE. The alteration in P/Q-type (α1A) VGCC immunoreactivity showed an inverse proportionality to that in PV immunoreactivity in the dentate gyrus and the CA1 region. These findings suggest that SE may induce prolonged up-regulation in P/Q-type VGCC expression within PV positive neurons.