|
|
||||||||
Journal of Neurophysiology, Vol 68, Issue 1 28-35, Copyright © 1992 by APS
ARTICLES |
A. Fukuda and D. A. Prince
Department of Neurology and Neurological Sciences, Stanford University School of Medicine, California 94305.
1. The effects of increased intracellular Ca2+ concentration ([Ca2+]i) on Na(+)-K+ pump activity in CA1 pyramidal neurons of rat hippocampal slices were investigated. The postglutamate hyperpolarization (PGH), which follows glutamate (GLU)-induced depolarization (GD), was used as an index of Na(+)-K+ pump activity, as was a ratio of PGH area to the preceding GD area (PGH ratio). 2. Perfusion of slices with saline containing Ca2+ ionophore (A23187, 10 microM) inhibited the PGH without producing apparent signs of cell deterioration. A 60-100% (85 +/- 15%, mean +/- SD) reduction in the PGH ratio occurred after 20-50 min of A23187 superfusion in 12 of 18 neurons tested. Complete abolition of the PGH occurred in 8 of these 12 cells exposed to A23187 for 30-120 min. 3. Application of A23187 in Ca(2+)-free/high-Mg2+ solution did not abolish the PGH, although small (less than 50%; 37 +/- 10%) reductions in the PGH ratio were observed after perfusion of 50 min or longer in five neurons tested. 4. Intracellular injection of the Ca2+ chelator bis-(o-amino-phenoxy)-N,N,N',N'-tetraacetic acid (BAPTA, 300-400 mM) blocked inhibition of the PGH by A23187. After 50 min of perfusion with Ca2+ ionophore, no reduction of the PGH ratio was observed in five neurons tested. 5. Rundown of the PGH without apparent change in membrane properties was observed in three neurons that were stable for greater than 2-3 h, allowing repetitive GLU applications. 6. Block of the PGH produced by a Na(+)-K(+)-adenosinetriphosphatase (ATPase) inhibitor (strophanthidin) prolonged the duration of GDs because of a delay in repolarization.(ABSTRACT TRUNCATED AT 250 WORDS)
This article has been cited by other articles:
![]() |
S. Avramescu and I. Timofeev Synaptic Strength Modulation after Cortical Trauma: A Role in Epileptogenesis J. Neurosci., July 2, 2008; 28(27): 6760 - 6772. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Kovacs, S. Schuchmann, S. Gabriel, O. Kann, J. Kardos, and U. Heinemann Free Radical-Mediated Cell Damage After Experimental Status Epilepticus in Hippocampal Slice Cultures J Neurophysiol, December 1, 2002; 88(6): 2909 - 2918. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Amzica and M. Massimini Glial and Neuronal Interactions during Slow Wave and Paroxysmal Activities in the Neocortex Cereb Cortex, October 1, 2002; 12(10): 1101 - 1113. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Li and D. A. Prince Synaptic Activity in Chronically Injured, Epileptogenic Sensory-Motor Neocortex J Neurophysiol, July 1, 2002; 88(1): 2 - 12. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. T. Ross and I. Soltesz Selective Depolarization of Interneurons in the Early Posttraumatic Dentate Gyrus: Involvement of the Na+/K+-ATPase J Neurophysiol, May 1, 2000; 83(5): 2916 - 2930. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Schuchmann, K. Buchheim, H. Meierkord, and U. Heinemann A Relative Energy Failure Is Associated With Low-Mg2+ But Not With 4-Aminopyridine Induced Seizure-Like Events in Entorhinal Cortex J Neurophysiol, January 1, 1999; 81(1): 399 - 403. [Abstract] [Full Text] [PDF] |
||||
![]() |
F.-S. Lo, R. J. Cork, and R. R. Mize Physiological Properties of Neurons in the Optic Layer of the Rat's Superior Colliculus J Neurophysiol, July 1, 1998; 80(1): 331 - 343. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Fukuda, K. Muramatsu, A. Okabe, Y. Shimano, H. Hida, I. Fujimoto, and H. Nishino NMDA Receptor-Mediated Differential Laminar Susceptibility to the Intracellular Ca2+ Accumulation Induced by Oxygen-Glucose Deprivation in Rat Neocortical Slices J Neurophysiol, January 1, 1998; 79(1): 430 - 438. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. V. Nguyen, L. Marin, and H. L. Atwood Synaptic Physiology and Mitochondrial Function in Crayfish Tonic and Phasic Motor Neurons J Neurophysiol, July 1, 1997; 78(1): 281 - 294. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. J. Tavalin, E. F. Ellis, and L. S. Satin Inhibition of the Electrogenic Na Pump Underlies Delayed Depolarization of Cortical Neurons After Mechanical Injury or Glutamate J Neurophysiol, February 1, 1997; 77(2): 632 - 638. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. T. Ross and I. Soltesz Long-term plasticity in interneurons of the dentate gyrus PNAS, July 17, 2001; 98(15): 8874 - 8879. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |