|
|
||||||||
Department of Physiology, Saga Medical School, Japan.
1. A rise in intracellular Ca2+ ([Ca2+]i) and a Ca2+ current (ICa) induced by a depolarizing pulse were simultaneously recorded by fura-2 or indo-1 fluorescence and whole-cell patch clamp techniques in cultured bullfrog sympathetic ganglion cells. 2. [Ca2+]i (calculated from the ratio of fura-2 fluorescences excited at 380 and 340 nm and recorded with a photomultiplier at > 492 nm) rose regeneratively (in most cells) during a command pulse (from -60 to 0 mV, 100 ms), continued to rise thereafter, peaked at 666 ms (on average) and decayed slowly with a half-decay time of 22.8 s. 3. Scanning a single horizontal line across the cytoplasm with an ultraviolet argon ion laser (351 nm) and recording indo-1 fluorescences at two wavelengths (peaked at 410 and 475 nm) with a confocal microscope demonstrated that [Ca2+]i beneath the cell membrane rose much faster than that in the deeper cytoplasm. The time course of the spatial integral of [Ca2+]i, however, corresponded well with that recorded with fura-2 fluorescence using a photomultiplier. 4. [Ca2+]i measured by fura-2 fluorescence ratio using a photomultiplier did not increase during a strong depolarizing pulse (-60 to +80 mV), but sometimes rose after the pulse. A depolarization-induced rise in [Ca2+]i ([Ca2+]i transient) was blocked in a Ca(2+)-free, EGTA solution, reduced by lowering the extracellular Ca2+ concentration ([Ca2+]o) to 0.45 or 0.9 mM and enhanced by raising [Ca2+]o to 7.2 or 14.4 nM. 5. The extracellular Ca2+ dependence was non-linear when long depolarizing pulses (up to 500 ms) were applied; the amplitude of [Ca2+]i transient/Ca2+ entry (unit [Ca2+]i transient) increased with an increase in Ca2+ entry. 6. Increasing the duration of depolarization (-50 or -60 to 0 mV) from 20 to 500 ms enhanced asymptotically the integral of ICa (due to inactivation), and progressively the magnitude of [Ca2+]i transients, leading to the apparent non-linear dependence of unit [Ca2+]i transient on Ca2+ entry as well as on the duration of membrane depolarization. The peak time of [Ca2+]i transient was unchanged for pulse durations up to 300 ms, but prolonged with an increase in pulse duration to 500 ms. 7. Inhibitors of Ca2+ release from intracellular Ca2+ reservoirs, dantrolene (10 microM) and ryanodine (50 microM), blocked the [Ca2+]i transient to 56 and 30%, respectively, of the control. 8. The higher the basal [Ca2+]i level, the greater was the magnitude of the [Ca2+]i transients.(ABSTRACT TRUNCATED AT 400 WORDS)
This article has been cited by other articles:
![]() |
T. Akita and K. Kuba Ca2+-dependent inactivation of Ca2+-induced Ca2+ release in bullfrog sympathetic neurons J. Physiol., July 15, 2008; 586(14): 3365 - 3384. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. E. Geiger and N. S. Magoski Ca2+-Induced Ca2+ Release in Aplysia Bag Cell Neurons Requires Interaction Between Mitochondrial and Endoplasmic Reticulum Stores J Neurophysiol, July 1, 2008; 100(1): 24 - 37. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Patterson, J. Sneyd, and D. D. Friel Depolarization-induced Calcium Responses in Sympathetic Neurons: Relative Contributions from Ca2+ Entry, Extrusion, ER/Mitochondrial Ca2+ Uptake and Release, and Ca2+ Buffering J. Gen. Physiol., January 1, 2007; 129(1): 29 - 56. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Suryanarayanan and M. M. Slaughter Synaptic Transmission Mediated by Internal Calcium Stores in Rod Photoreceptors J. Neurosci., February 8, 2006; 26(6): 1759 - 1766. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Verkhratsky Physiology and Pathophysiology of the Calcium Store in the Endoplasmic Reticulum of Neurons Physiol Rev, January 1, 2005; 85(1): 201 - 279. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Tully and S. N. Treistman Distinct Intracellular Calcium Profiles Following Influx Through N- Versus L-Type Calcium Channels: Role of Ca2+-Induced Ca2+ Release J Neurophysiol, July 1, 2004; 92(1): 135 - 143. [Abstract] [Full Text] [PDF] |
||||
![]() |
Z. Cseresnyes and M. F. Schneider Peripheral Hot Spots for Local Ca2+ Release after Single Action Potentials in Sympathetic Ganglion Neurons Biophys. J., January 1, 2004; 86(1): 163 - 181. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Gu, K. Kwong, and L.-Y. Lee Ca2+ Transient Evoked by Chemical Stimulation Is Enhanced by PGE2 in Vagal Sensory Neurons: Role of cAMP/PKA Signaling Pathway J Neurophysiol, April 1, 2003; 89(4): 1985 - 1993. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Sukhareva, S. V. Smith, D. Maric, and J. L. Barker Functional Properties of Ryanodine Receptors in Hippocampal Neurons Change During Early Differentiation in Culture J Neurophysiol, September 1, 2002; 88(3): 1077 - 1087. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. Albrecht, S. L. Colegrove, and D. D. Friel Differential Regulation of ER Ca2+ Uptake and Release Rates Accounts for Multiple Modes of Ca2+-induced Ca2+ Release J. Gen. Physiol., February 22, 2002; 119(3): 211 - 233. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. S. Scornik, L. A. Merriam, and R. L. Parsons Number of KCa Channels Underlying Spontaneous Miniature Outward Currents (SMOCs) in Mudpuppy Cardiac Neurons J Neurophysiol, January 1, 2001; 85(1): 54 - 60. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. I. McDonough, Z. Cseresnyes, and M. F. Schneider Origin Sites of Calcium Release and Calcium Oscillations in Frog Sympathetic Neurons J. Neurosci., December 15, 2000; 20(24): 9059 - 9070. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Hillsley, J. L. Kenyon, and T. K. Smith Ryanodine-Sensitive Stores Regulate the Excitability of AH Neurons in the Myenteric Plexus of Guinea-Pig Ileum J Neurophysiol, December 1, 2000; 84(6): 2777 - 2785. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Krizaj, J.-X. Bao, Y. Schmitz, P. Witkovsky, and D. R. Copenhagen Caffeine-Sensitive Calcium Stores Regulate Synaptic Transmission from Retinal Rod Photoreceptors J. Neurosci., September 1, 1999; 19(17): 7249 - 7261. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. A. Merriam, F. S. Scornik, and R. L. Parsons Ca2+-Induced Ca2+ Release Activates Spontaneous Miniature Outward Currents (SMOCs) in Parasympathetic Cardiac Neurons J Neurophysiol, August 1, 1999; 82(2): 540 - 550. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. B. Pivovarova, J. Hongpaisan, S. B. Andrews, and D. D. Friel Depolarization-Induced Mitochondrial Ca Accumulation in Sympathetic Neurons: Spatial and Temporal Characteristics J. Neurosci., August 1, 1999; 19(15): 6372 - 6384. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. T. Alonso, M. J. Barrero, P. Michelena, E. Carnicero, I. Cuchillo, A. G. Garcia, J. Garcia-Sancho, M. Montero, and J. Alvarez Ca2+-induced Ca2+ Release in Chromaffin Cells Seen from inside the ER with Targeted Aequorin J. Cell Biol., January 25, 1999; 144(2): 241 - 254. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. M. Usachev and S. A. Thayer All-or-None Ca2+ Release from Intracellular Stores Triggered by Ca2+ Influx through Voltage-Gated Ca2+ Channels in Rat Sensory Neurons J. Neurosci., October 1, 1997; 17(19): 7404 - 7414. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. M. Empson and A. Galione Cyclic ADP-ribose Enhances Coupling between Voltage-gated Ca2+ Entry and Intracellular Ca2+ Release J. Biol. Chem., August 22, 1997; 272(34): 20967 - 20970. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |