Voltage-clamp recordings from identified dissociated neuroendocrine cells of the adult rat supraoptic nucleus.

In vitro intracellular recordings of membrane potential obtained from the oxytocin and vasopressin neurons of the mammalian hypothalamo-neurohypophysial system in slices (1-3) and expiants (4, 5) have demonstrated many of the intrinsic properties of these magnocellular neuroendocrine cells (MNCs). Voltage-clamp techniques, which are required to study directly the currents underlying intrinsic or transmitter-evoked potential changes, have been applied to cultured embryonic (6) or neonatal supraoptic neurons (7-9) and have been successfully applied to adult supraoptic neurons in situ in only one laboratory (10, 11). We have modified a technique for dissociation of viable adult guineapig hippocampal neurons (12) to dissociate supraoptic MNCs from adult rats for voltage-clamp studies. MNCs were selectively labelled with a fluorescent dye in vivo so that they could be identified after dissociation and prior to making recordings. These data have been published in abstract form elsewhere (13, 14).