|
|
||||||||
Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112, USA.
1. The effects of NO donors on Ca2+ channel currents and noradrenaline (NA)-induced Ca2+ current inhibition were investigated in superior cervical ganglion (SCG) neurons using the whole-cell patch-clamp technique. 2. A 500 microM concentration of the NO donors, sodium nitroprusside (SNP) and S-nitroso-N-acetylpenicillamine (SNAP), enhanced Ca2+ current amplitude after either extracellular or intracellular application. The magnitude of Ca2+ current enhancement induced by NO donors was greater after intracellular application than after extracellular application. 3. Intracellular application of 1 mM guanosine 3',5'-cyclic monophosphate (cGMP) or 100 microM M&B 22948 (2-O-propoxyphenyl-8-azapurine-6-one), a cGMP phosphodiesterase inhibitor, or extracellular application of 1 mM 8-bromoguanosine 3',5'-cyclic monophosphate (8-Br-cGMP) also increased the amplitude of Ca2+ currents thus mimicking the effect of the NO donors on Ca2+ channels. In contrast, pretreatment with Methylene Blue (100 microM) decreased the SNP (500 microM)-induced enhancement of Ca2+ currents. 4. Intracellular application of 500 microM SNP and SNAP, 100 microM M&B 22948 or 1 mM cGMP, or extracellular application of 200 microM 8-Br-cGMP reduced the magnitude of Ca2+ current inhibition induced by 5 microM NA. In addition, 500 microM SNP prevented the NA-induced shift of tail current activation curves to more depolarized potentials. 5. Internal dialysis with 500 microM SNP and SNAP or 1 mM cGMP, or extracellular application of 200 microM 8-Br-cGMP, reduced Ca2+ current facilitation produced by a depolarizing conditioning pulse both in the absence and presence of 5 microM NA. 6. The results suggest that NO donors induce enhancement of Ca2+ currents and block NA-induced Ca2+ current inhibition of SCG neurons via stimulation of cGMP formation.
This article has been cited by other articles:
![]() |
G. Tolstykh, P. M. de Paula, and S. Mifflin Voltage-Dependent Calcium Currents Are Enhanced in Nucleus of the Solitary Tract Neurons Isolated From Renal Wrap Hypertensive Rats Hypertension, May 1, 2007; 49(5): 1163 - 1169. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Almanza, F. Navarrete, R. Vega, and E. Soto Modulation of Voltage-Gated Ca2+ Current in Vestibular Hair Cells by Nitric Oxide J Neurophysiol, February 1, 2007; 97(2): 1188 - 1195. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. M. Mbaku, L. Zhang, W. J. Pearce, S. P. Duckles, and J. Buchholz Chronic hypoxia alters the function of NOS nerves in cerebral arteries of near-term fetal and adult sheep J Appl Physiol, February 1, 2003; 94(2): 724 - 732. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. D'Ascenzo, G. Martinotti, G. B. Azzena, and C. Grassi cGMP/Protein Kinase G-Dependent Inhibition of N-Type Ca2+ Channels Induced by Nitric Oxide in Human Neuroblastoma IMR32 Cells J. Neurosci., September 1, 2002; 22(17): 7485 - 7492. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Yoshimura, S. Seki, and W. C. de Groat Nitric Oxide Modulates Ca2+ Channels in Dorsal Root Ganglion Neurons Innervating Rat Urinary Bladder J Neurophysiol, July 1, 2001; 86(1): 304 - 311. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. N. Mbaku, L. Zhang, S. P. Duckles, and J. Buchholz Nitric-Oxide Synthase-Containing Nerves Facilitate Adrenergic Transmitter Release in Sheep Middle Cerebral Arteries J. Pharmacol. Exp. Ther., May 1, 2000; 293(2): 397 - 402. [Abstract] [Full Text] |
||||
![]() |
A. Gelperin, J. Flores, F. Raccuia-Behling, and I.R.C. Cooke Nitric Oxide and Carbon Monoxide Modulate Oscillations of Olfactory Interneurons in a Terrestrial Mollusk J Neurophysiol, January 1, 2000; 83(1): 116 - 127. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. A. Summers, J. L. Overholt, and N. R. Prabhakar Nitric Oxide Inhibits L-Type Ca2+ Current in Glomus Cells of the Rabbit Carotid Body Via a cGMP-Independent Mechanism J Neurophysiol, April 1, 1999; 81(4): 1449 - 1457. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Buchholz, K. Edwards-Teunissen, and S. P. Duckles Impact of development and chronic hypoxia on NE release from adrenergic nerves in sheep arteries Am J Physiol Regulatory Integrative Comp Physiol, March 1, 1999; 276(3): R799 - R808. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Marrannes, E. D. Prins, and G. Clincke Influence of Lubeluzole on Voltage-Sensitive Ca++ Channels in Isolated Rat Neurons J. Pharmacol. Exp. Ther., July 1, 1998; 286(1): 201 - 214. [Abstract] [Full Text] |
||||
![]() |
P. Shrager, A. W. Custer, K. Kazarinova, M. N. Rasband, and D. Mattson Nerve Conduction Block by Nitric Oxide That Is Mediated by the Axonal Environment J Neurophysiol, February 1, 1998; 79(2): 529 - 536. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |