title: Dual role for calcium in the control of spike duration in rat supraoptic neuroendocrine cells.
abstract: Magnocellular neurosecretory cells (MNCs) display activity-dependent changes in spike duration to modulate Ca2+ influx both in their somata, and in their axon terminals in the neurohypophysis. This study reveals (i) that Ca2+ influx is required to mediate the expression of spike broadening, and (ii) that internal Ca2+ activates a delayed component of spike repolarization in MNCs of the rat supraoptic nucleus. This mechanism provides a rapid feedback control of spike-mediated Ca2+ influx in these neuroendocrine cells.
authors.affiliation: Centre for Research in Neuroscience, Montreal General Hospital, Que., Canada.
authors.forename: K
authors.initials: K
authors.lastname: Kirkpatrick
authors.forename: C W
authors.initials: CW
authors.lastname: Bourque
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002118:Calcium / Q000494:pharmacology / Q000502:physiology*; D002586:Cesium / Q000494:pharmacology; D004533:Egtazic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D007700:Kinetics; D009490:Neurosecretory Systems / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D009924:Organ Culture Techniques; D051381:Rats; D013495:Supraoptic Nucleus / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000494:pharmacology
chemical_list: D013757:Tetraethylammonium Compounds; D002586:Cesium; D004533:Egtazic Acid; D019789:Tetraethylammonium; C025603:1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid; D002118:Calcium