| KCNQ/M-currents contribute to the resting membrane potential in rat visceral sensory neurons. | |
| | |
MedLine Citation:
|
PMID: 16777937 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
The M-current is a slowly activating, non-inactivating potassium current that has been shown to be present in numerous cell types. In this study, KCNQ2, Q3 and Q5, the molecular correlates of M-current in neurons, were identified in the visceral sensory neurons of the nodose ganglia from rats through immunocytochemical studies. All neurons showed expression of each of the three proteins. In voltage clamp studies, the cognition-enhancing drug linopirdine (1-50 microM) and its analogue, XE991 (10 microM), quickly and irreversibly blocked a small, slowly activating current that had kinetic properties similar to KCNQ/M-currents. This current activated between -60 and -55 mV, had a voltage-dependent activation time constant of 208 +/- 12 ms at -20 mV, a deactivation time constant of 165 +/- 24 ms at -50 mV and V1/2 of -24 +/- 2 mV, values which are consistent with previous reports for endogenous M-currents. In current clamp studies, these drugs also led to a depolarization of the resting membrane potential at values as negative as -60 mV. Flupirtine (10-20 microM), an M-current activator, caused a 3-14 mV leftward shift in the current-voltage relationship and also led to a hyperpolarization of resting membrane potential. These data indicate that the M-current is present in nodose neurons, is activated at resting membrane potential and that it is physiologically important in regulating excitability by maintaining cells at negative voltages. |
| | |
Authors:
|
Cynthia L Wladyka; Diana L Kunze |
Related Documents
:
|
10930547 - The kinetics of a non-inactivating k(+) current in alphat3-1 pituitary gonadotropes is ... 853287 - The effect of extracellular potassium on the intracellular potassium ion activity and t... 10497907 - Eicosapentaenoic acid inhibits vasopressin-activated ca2+ influx and cell proliferation... 1238977 - Dual effects of calcium ions on pacemaker activity in guinea-pig taenia coli. 2174697 - External electric fields stimulate the electrogenic calcium/sodium exchange in plant pr... 12052527 - Quantal endplate currents from newborn to adult mice and the switch from embryonic to a... |
Publication Detail:
|
Type: Journal Article; Research Support, N.I.H., Extramural Date: 2006-06-15 |
Journal Detail:
|
Title: The Journal of physiology Volume: 575 ISSN: 0022-3751 ISO Abbreviation: J. Physiol. (Lond.) Publication Date: 2006 Aug |
Date Detail:
|
Created Date: 2006-08-16 Completed Date: 2006-10-06 Revised Date: 2009-11-18 |
Medline Journal Info:
|
Nlm Unique ID: 0266262 Medline TA: J Physiol Country: England |
Other Details:
|
Languages: eng Pagination: 175-89 Citation Subset: IM |
Affiliation:
|
Rammelkamp Centre for Research and Education R326 MetroHealth Medical Centre, 2500 MetroHealth Drive, Cleveland, OH 44109-1998, USA. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Aminopyridines
/
pharmacology Animals Anthracenes / pharmacology Cells, Cultured Dose-Response Relationship, Drug Indoles / pharmacology KCNQ Potassium Channels / analysis, drug effects, metabolism* KCNQ2 Potassium Channel / analysis, drug effects, metabolism* KCNQ3 Potassium Channel / analysis, drug effects, metabolism* Membrane Potentials Neurons, Afferent / chemistry, drug effects, metabolism* Nodose Ganglion / chemistry, drug effects, physiology* Potassium / metabolism Potassium Channel Blockers / pharmacology Pyridines / pharmacology Rats Rats, Sprague-Dawley Visceral Afferents / chemistry, drug effects, metabolism* |
| Grant Support | |
ID/Acronym/Agency:
|
HL25830/HL/NHLBI NIH HHS; HL61436/HL/NHLBI NIH HHS |
| Chemical | |
Reg. No./Substance:
|
0/10,10-bis(4-pyridinylmethyl)-9(10H)-anthracenone; 0/Aminopyridines; 0/Anthracenes; 0/Indoles; 0/KCNQ Potassium Channels; 0/KCNQ2 Potassium Channel; 0/KCNQ3 Potassium Channel; 0/Kcnq2 protein, rat; 0/Kcnq3 protein, rat; 0/Kcnq5 protein, rat; 0/Potassium Channel Blockers; 0/Pyridines; 105431-72-9/linopirdine; 56995-20-1/flupirtine; 7440-09-7/Potassium |
| Comments/Corrections | |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Angiotensin II regulates neuronal excitability via phosphatidylinositol 4,5-bisphosphate-dependent m...
Next Document: Chronic intermittent hypoxia induces hypoxia-evoked catecholamine efflux in adult rat adrenal medull...