QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

This Article Full Text Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (59) Citing Articles via Google Scholar Google Scholar Articles by Sah, P. Articles by Clements, J. D. Search for Related Content PubMed PubMed Citation Articles by Sah, P. Articles by Clements, J. D. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB CALCIUM COMPOUNDS CALCIUM, ELEMENTAL

 Previous Article  |  Next Article 

The Journal of Neuroscience, May 15, 1999, 19(10):3657-3664

Photolytic Manipulation of [Ca²⁺]_i Reveals Slow Kinetics of Potassium Channels Underlying the Afterhyperpolarization in Hipppocampal Pyramidal Neurons

Pankaj Sah and John D. Clements

Division of Neuroscience, John Curtin School of Medical Research, Australian National University, Canberra ACT 2601, Australia

The identity of the potassium channel underlying the slow, apamin-insensitive component of the afterhyperpolarization current (sI_AHP) remains unknown. We studied sI_AHP in CA1 pyramidal neurons using simultaneous whole-cell recording, calcium fluorescence imaging, and flash photolysis of caged compounds. Intracellular calcium concentration ([Ca²⁺]_i) peaked earlier and decayed more rapidly than sI_AHP. Loading cells with low concentrations of the calcium chelator EGTA slowed the activation and decay of sI_AHP. In the presence of EGTA, intracellular calcium decayed with two time constants. When [Ca²⁺]_i was increased rapidly after photolysis of DM-Nitrophen, both apamin-sensitive and apamin-insensitive outward currents were activated. The apamin-sensitive current activated rapidly (<20 msec), whereas the apamin-insensitive current activated more slowly (180 msec). The apamin-insensitive current was reduced by application of serotonin and carbachol, confirming that it was caused by sI_AHP channels. When [Ca²⁺]_i was decreased rapidly via photolysis of diazo-2, the decay of sI_AHP was similar to control (1.7 sec). All results could be reproduced by a model potassium channel gated by calcium, suggesting that the channels underlying sI_AHP have intrinsically slow kinetics because of their high affinity for calcium.

Key words: afterhyperpolarization; intracellular calcium concentration; potassium channel; hippocampus; pyramidal neurons; current

---

Copyright © 1999 Society for Neuroscience  0270-6474/99/19103657-08$05.00/0

This article has been cited by other articles:

				J. A. Goldberg, M. A. Teagarden, R. C. Foehring, and C. J. Wilson Nonequilibrium Calcium Dynamics Regulate the Autonomous Firing Pattern of Rat Striatal Cholinergic Interneurons J. Neurosci., July 1, 2009; 29(26): 8396 - 8407. [Abstract] [Full Text] [PDF]

				E. A. Matthews, A. P. Weible, S. Shah, and J. F. Disterhoft The BK-mediated fAHP is modulated by learning a hippocampus-dependent task PNAS, September 30, 2008; 105(39): 15154 - 15159. [Abstract] [Full Text] [PDF]

				A. D. Powell, E. C. Toescu, J. Collinge, and J. G. R. Jefferys Alterations in Ca2+-Buffering in Prion-Null Mice: Association with Reduced Afterhyperpolarizations in CA1 Hippocampal Neurons J. Neurosci., April 9, 2008; 28(15): 3877 - 3886. [Abstract] [Full Text] [PDF]

				J. M. Power and P. Sah Competition between Calcium-Activated K+ Channels Determines Cholinergic Action on Firing Properties of Basolateral Amygdala Projection Neurons J. Neurosci., March 19, 2008; 28(12): 3209 - 3220. [Abstract] [Full Text] [PDF]

				J. M. Power and P. Sah Distribution of IP3-mediated calcium responses and their role in nuclear signalling in rat basolateral amygdala neurons J. Physiol., May 1, 2007; 580(3): 835 - 857. [Abstract] [Full Text] [PDF]

				T. Kelly and J. Church Relationships Between Calcium and pH in the Regulation of the Slow Afterhyperpolarization in Cultured Rat Hippocampal Neurons J Neurophysiol, November 1, 2006; 96(5): 2342 - 2353. [Abstract] [Full Text] [PDF]

				J. M. Power and P. Sah Intracellular calcium store filling by an L-type calcium current in the basolateral amygdala at subthreshold membrane potentials J. Physiol., January 15, 2005; 562(2): 439 - 453. [Abstract] [Full Text] [PDF]

				W. W. Wu, C. S. Chan, and J. F. Disterhoft Slow Afterhyperpolarization Governs the Development of NMDA Receptor-Dependent Afterdepolarization in CA1 Pyramidal Neurons During Synaptic Stimulation J Neurophysiol, October 1, 2004; 92(4): 2346 - 2356. [Abstract] [Full Text] [PDF]

				M. Ghamari-Langroudi and C. W. Bourque Muscarinic Receptor Modulation of Slow Afterhyperpolarization and Phasic Firing in Rat Supraoptic Nucleus Neurons J. Neurosci., September 1, 2004; 24(35): 7718 - 7726. [Abstract] [Full Text] [PDF]

				C. T. Bond, P. S. Herson, T. Strassmaier, R. Hammond, R. Stackman, J. Maylie, and J. P. Adelman Small Conductance Ca2+-Activated K+ Channel Knock-Out Mice Reveal the Identity of Calcium-Dependent Afterhyperpolarization Currents J. Neurosci., June 9, 2004; 24(23): 5301 - 5306. [Abstract] [Full Text] [PDF]

				Q.-s. Liu, Q. Xu, G. Arcuino, J. Kang, and M. Nedergaard From The Cover: Astrocyte-mediated activation of neuronal kainate receptors PNAS, March 2, 2004; 101(9): 3172 - 3177. [Abstract] [Full Text] [PDF]

				H. J. Abel, J.C.F. Lee, J. C. Callaway, and R. C. Foehring Relationships Between Intracellular Calcium and Afterhyperpolarizations in Neocortical Pyramidal Neurons J Neurophysiol, January 1, 2004; 91(1): 324 - 335. [Abstract] [Full Text]

				M.C.W. van Rossum, B. J. O'Brien, and R. G. Smith Effects of Noise on the Spike Timing Precision of Retinal Ganglion Cells J Neurophysiol, May 1, 2003; 89(5): 2406 - 2419. [Abstract] [Full Text] [PDF]

				X. Sun, X. Q. Gu, and G. G. Haddad Calcium Influx via L- and N-Type Calcium Channels Activates a Transient Large-Conductance Ca2+-Activated K+ Current in Mouse Neocortical Pyramidal Neurons J. Neurosci., May 1, 2003; 23(9): 3639 - 3648. [Abstract] [Full Text] [PDF]

				F. Vogalis, J. R Harvey, and J. B Furness PKA-mediated inhibition of a novel K+ channel underlies the slow after-hyperpolarization in enteric AH neurons J. Physiol., May 1, 2003; 548(3): 801 - 814. [Abstract] [Full Text] [PDF]

				R. W. Stackman, R. S. Hammond, E. Linardatos, A. Gerlach, J. Maylie, J. P. Adelman, and T. Tzounopoulos Small Conductance Ca2+-Activated K+ Channels Modulate Synaptic Plasticity and Memory Encoding J. Neurosci., December 1, 2002; 22(23): 10163 - 10171. [Abstract] [Full Text] [PDF]

				M. M. Shah and D. G. Haylett K+ Currents Generated by NMDA Receptor Activation in Rat Hippocampal Pyramidal Neurons J Neurophysiol, June 1, 2002; 87(6): 2983 - 2989. [Abstract] [Full Text] [PDF]

				J.-M. Goaillard and P. Vincent Serotonin suppresses the slow afterhyperpolarization in rat intralaminar and midline thalamic neurones by activating 5-HT7 receptors J. Physiol., June 1, 2002; 541(2): 453 - 465. [Abstract] [Full Text] [PDF]

				J. M. Power and P. Sah Nuclear Calcium Signaling Evoked by Cholinergic Stimulation in Hippocampal CA1 Pyramidal Neurons J. Neurosci., May 1, 2002; 22(9): 3454 - 3462. [Abstract] [Full Text] [PDF]

				E. S. L. Faber and P. Sah Physiological Role of Calcium-Activated Potassium Currents in the Rat Lateral Amygdala J. Neurosci., March 1, 2002; 22(5): 1618 - 1628. [Abstract] [Full Text] [PDF]

				F. Vogalis, J. R Harvey, and J. B Furness TEA- and apamin-resistant KCa channels in guinea-pig myenteric neurons: slow AHP channels J. Physiol., January 15, 2002; 538(2): 421 - 433. [Abstract] [Full Text] [PDF]

				T. Tabata and M. Kano Heterogeneous Intrinsic Firing Properties of Vertebrate Retinal Ganglion Cells J Neurophysiol, January 1, 2002; 87(1): 30 - 41. [Abstract] [Full Text] [PDF]

				F. Vogalis, J. B. Furness, and W. A. A. Kunze Afterhyperpolarization Current in Myenteric Neurons of the Guinea Pig Duodenum J Neurophysiol, May 1, 2001; 85(5): 1941 - 1951. [Abstract] [Full Text] [PDF]

				C.-C. Shieh, M. Coghlan, J. P. Sullivan, and M. Gopalakrishnan Potassium Channels: Molecular Defects, Diseases, and Therapeutic Opportunities Pharmacol. Rev., December 1, 2000; 52(4): 557 - 594. [Abstract] [Full Text] [PDF]

				R. Kurtz, V. Durr, and M. Egelhaaf Dendritic Calcium Accumulation Associated With Direction-Selective Adaptation in Visual Motion-Sensitive Neurons In Vivo J Neurophysiol, October 1, 2000; 84(4): 1914 - 1923. [Abstract] [Full Text] [PDF]

				T. Aoki and S. C. Baraban Properties of a Calcium-Activated K+ Current on Interneurons in the Developing Rat Hippocampus J Neurophysiol, June 1, 2000; 83(6): 3453 - 3461. [Abstract] [Full Text] [PDF]

				B Lancaster and A M Batchelor Novel action of BAPTA series chelators on intrinsic K+ currents in rat hippocampal neurones J. Physiol., January 15, 2000; 522(2): 231 - 246. [Abstract] [Full Text] [PDF]

				M. Tanabe, M. Mori, B. H. Gahwiler, and U. Gerber Apamin-Sensitive Conductance Mediates the K+ Current Response During Chemical Ischemia in CA3 Pyramidal Cells J Neurophysiol, December 1, 1999; 82(6): 2876 - 2882. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help