 |
||||
|
||||
|
||||
|
||||
Previous Article | Next Article
Volume 16, Number 14, Issue of July 15, 1996 pp. 4383-4388
Copyright ©1996 Society for NeuroscienceProtein Kinase A Activation Increases Sodium Current Magnitude in the Electric Organ of Sternopygus
Received Feb. 1, 1996; revised April 8, 1996; accepted April 23, 1996.
Lynne McAnelly and Harold H. Zakon Department of Zoology and Center for Developmental Biology, The University of Texas at Austin, Austin, Texas 78712
The inactivation kinetics of the Na+ current of the weakly electric fish Sternopygus are modified by treatment with androgens. To determine whether phosphorylation could play a role in this effect, we examined whether activation of protein kinase A by 8 bromo cyclic AMP (8 Br cAMP) altered voltage-dependent properties of the current. Using a two-electrode voltage-clamp procedure, we found no effect of 8 Br cAMP on inactivation kinetics or other voltage-dependent properties of the Na+ current of the electrocytes. However, treatment with 8 Br cAMP did produce a dose-dependent increase in the Na+ current compared with saline controls: 17.6% at 100 µM, 42.4% at 1 mM, and 43.1% at 5 mM. This effect was blocked by 30 µM H89, a PKA inhibitor, indicating that the observed effect was attributable to 8 Br cAMP activation of PKA. We conclude that androgen-induced changes in Na+ current inactivation are not mediated by PKA and suggest that PKA-mediated increases in Na+ current underlie increases in the amplitude of the electric organ discharge observed in social interactions or with changes in water conductance.
Key words: protein kinase A; sodium channel; phosphorylation; cyclic adenosine monophosphate; 8 Br cAMP; electric fish; electric organ
This article has been cited by other articles:
M. R. Markham and P. K. Stoddard
Adrenocorticotropic Hormone Enhances the Masculinity of an Electric Communication Signal by Modulating the Waveform and Timing of Action Potentials within Individual Cells
J. Neurosci., September 21, 2005; 25(38): 8746 - 8754.
[Abstract] [Full Text] [PDF]
W. J. Moody and M. M. Bosma
Ion Channel Development, Spontaneous Activity, and Activity-Dependent Development in Nerve and Muscle Cells
Physiol Rev, July 1, 2005; 85(3): 883 - 941.
[Abstract] [Full Text] [PDF]
P. K. Stoddard, M. R. Markham, and V. L. Salazar
Serotonin modulates the electric waveform of the gymnotiform electric fish Brachyhypopomus pinnicaudatus
J. Exp. Biol., April 15, 2003; 206(8): 1353 - 1362.
[Abstract] [Full Text] [PDF]
G. F. Lopreato, Y. Lu, A. Southwell, N. S. Atkinson, D. M. Hillis, T. P. Wilcox, and H. H. Zakon
Evolution and divergence of sodium channel genes in vertebrates
PNAS, June 19, 2001; 98(13): 7588 - 7592.
[Abstract] [Full Text] [PDF]
M. L. McAnelly and H. H. Zakon
Coregulation of Voltage-Dependent Kinetics of Na+ and K+ Currents in Electric Organ
J. Neurosci., May 1, 2000; 20(9): 3408 - 3414.
[Abstract] [Full Text] [PDF]
H Zakon, L Mcanelly, G. Smith, K Dunlap, G Lopreato, J Oestreich, and W. Few
Plasticity of the electric organ discharge: implications for the regulation of ionic currents
J. Exp. Biol., January 5, 1999; 202(10): 1409 - 1416.
[Abstract] [PDF]
K. D. Dunlap, M. L. McAnelly, and H. H. Zakon
Estrogen Modifies an Electrocommunication Signal by Altering the Electrocyte Sodium Current in an Electric Fish, Sternopygus
J. Neurosci., April 15, 1997; 17(8): 2869 - 2875.
[Abstract] [Full Text] [PDF]
|
|
|
|
 |
|