Whole cell voltage clamp recordings from cultured neurons of the supraoptic area of neonatal rat hypothalamus.

Whole-cell voltage and current clamp recordings were made from cultured neurons from the hypothalamic supraoptic area of neonatal rats. These neurons fired spontaneous Na+-action potentials, appearing as mixed Na+/K+-currents in voltage clamp. Isolated Na+-currents (less than 3 nA) were rapidly activated and inactivated during positive potential pulses from -80 mV. Two voltage-activated Ba2+-currents (less than 1 nA) were also recorded. These techniques offer a promising new approach for studying the striking electrical behavior of cultured hypothalamic neurons.