Voltage-gated and synaptic currents in rat Purkinje cells in dissociated cell cultures

The electrical properties of rat Purkinje cells and synapses from granule cells were studied in dissociated cell cultures. To identify the cells we used an immunohistochemical method and recorded voltage-gated and synaptic currents with the patch-clamp technique (the whole-cell mode). Cultured Purkinje cells generated action potentials similar to those recorded from in vitro slices or in vivo preparations. Early Na, late Ca inward current, and K outward currents were distinguished by ion substitution under voltage clamp. We also recorded spontaneous synaptic currents in Purkinje cells cultured with granule cells. These synaptic currents reversed direction at the membrane potential of 2.5 mV, which was similar to currents induced by L-glutamate. Therefore, these are most likely excitatory synaptic currents from granule cells. Since these properties of Purkinje cells examined here are similar to those in situ, the cells in dissociated cell cultures offer a great opportunity to study biophysical properties of identified neurons in the central nervous system.