Activation of muscarinic K+ current in guinea-pig atrial myocytes
by sphingosine-1-phosphate
M. Bunemann, B. Brandts, D. zu Heringdorf, C. van Koppen, K. Jakobs, and L. Pott. J Physiol, (December 1995)Bunemann, M Brandts, B zu Heringdorf, D M van Koppen, C J Jakobs,
K H Pott, L In Vitro Research Support, Non-U.S. Gov't England The
Journal of physiology J Physiol. 1995 Dec 15;489 ( Pt 3):701-7..
Abstract
1. Activation of muscarinic K+ current (IK(ACh)) by sphingosine-1-phosphate
(Sph-1-P) was studied in isolated cultured guinea-pig atrial myocytes
using whole-cell voltage clamp. 2. Sph-1-P caused activation of IK(ACh)
with an EC50 of 1.2 nM. The maximal current that could be activated
by Sph-1-P amounted to about 90% of the IK(ACh) caused by a saturating
concentration of acetylcholine (ACh, 10 microM). Sphingosine (1 microM),
which can mimic the signalling effects of Sph-1-P in other cells,
failed to cause measurable activation of IK(ACh). 3. IK(ACh) activation
by Sph-1-P was completely suppressed in cells treated with pertussis
toxin. 4. Desensitization of muscarinic receptors by pre-incubation
of the cells with carbachol did not affect the response to Sph-1-P;
likewise, pre-incubation of the cells with Sph-1-P resulted in a
reduced sensitivity to the phospholipid but not to ACh. In contrast,
pre-incubation with either Sph-1-P or a serum phospholipid previously
described as activating atrial IK(ACh) resulted in reduced sensitivity
to both phospholipids. 5. It is concluded that activation of IK(ACh)
by Sph-1-P in atrial myocytes is induced by binding to a novel G
protein-coupled phospholipid receptor.
Bunemann, M Brandts, B zu Heringdorf, D M van Koppen, C J Jakobs,
K H Pott, L In Vitro Research Support, Non-U.S. Gov't England The
Journal of physiology J Physiol. 1995 Dec 15;489 ( Pt 3):701-7.
%0 Journal Article
%1 Bunemann1995
%A Bunemann, M.
%A Brandts, B.
%A zu Heringdorf, D. M.
%A van Koppen, C. J.
%A Jakobs, K. H.
%A Pott, L.
%D 1995
%J J Physiol
%K & *Lysophospholipids Acetylcholine/pharmacology Adenosine/pharmacology Agents/pharmacology Agonists/*pharmacology Animals Biotransformation/drug Cardiovascular Channels/drug Female GTP-Binding Guinea Heart/drug Male Membrane Muscarinic Myocardium/cytology/*metabolism Patch-Clamp Phospholipids/blood Pigs Potassium Potentials/drug Proteins/metabolism Signal Sphingosine/*analogs Techniques Transduction/drug derivatives/pharmacology effects effects/*metabolism effects/physiology
%P 701-7
%T Activation of muscarinic K+ current in guinea-pig atrial myocytes
by sphingosine-1-phosphate
%U http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=8788935
%V 489 ( Pt 3)
%X 1. Activation of muscarinic K+ current (IK(ACh)) by sphingosine-1-phosphate
(Sph-1-P) was studied in isolated cultured guinea-pig atrial myocytes
using whole-cell voltage clamp. 2. Sph-1-P caused activation of IK(ACh)
with an EC50 of 1.2 nM. The maximal current that could be activated
by Sph-1-P amounted to about 90% of the IK(ACh) caused by a saturating
concentration of acetylcholine (ACh, 10 microM). Sphingosine (1 microM),
which can mimic the signalling effects of Sph-1-P in other cells,
failed to cause measurable activation of IK(ACh). 3. IK(ACh) activation
by Sph-1-P was completely suppressed in cells treated with pertussis
toxin. 4. Desensitization of muscarinic receptors by pre-incubation
of the cells with carbachol did not affect the response to Sph-1-P;
likewise, pre-incubation of the cells with Sph-1-P resulted in a
reduced sensitivity to the phospholipid but not to ACh. In contrast,
pre-incubation with either Sph-1-P or a serum phospholipid previously
described as activating atrial IK(ACh) resulted in reduced sensitivity
to both phospholipids. 5. It is concluded that activation of IK(ACh)
by Sph-1-P in atrial myocytes is induced by binding to a novel G
protein-coupled phospholipid receptor.
@article{Bunemann1995,
abstract = {1. Activation of muscarinic K+ current (IK(ACh)) by sphingosine-1-phosphate
(Sph-1-P) was studied in isolated cultured guinea-pig atrial myocytes
using whole-cell voltage clamp. 2. Sph-1-P caused activation of IK(ACh)
with an EC50 of 1.2 nM. The maximal current that could be activated
by Sph-1-P amounted to about 90% of the IK(ACh) caused by a saturating
concentration of acetylcholine (ACh, 10 microM). Sphingosine (1 microM),
which can mimic the signalling effects of Sph-1-P in other cells,
failed to cause measurable activation of IK(ACh). 3. IK(ACh) activation
by Sph-1-P was completely suppressed in cells treated with pertussis
toxin. 4. Desensitization of muscarinic receptors by pre-incubation
of the cells with carbachol did not affect the response to Sph-1-P;
likewise, pre-incubation of the cells with Sph-1-P resulted in a
reduced sensitivity to the phospholipid but not to ACh. In contrast,
pre-incubation with either Sph-1-P or a serum phospholipid previously
described as activating atrial IK(ACh) resulted in reduced sensitivity
to both phospholipids. 5. It is concluded that activation of IK(ACh)
by Sph-1-P in atrial myocytes is induced by binding to a novel G
protein-coupled phospholipid receptor.},
added-at = {2010-12-14T18:12:02.000+0100},
author = {Bunemann, M. and Brandts, B. and zu Heringdorf, D. M. and van Koppen, C. J. and Jakobs, K. H. and Pott, L.},
biburl = {https://www.bibsonomy.org/bibtex/2943744138da616404cc303502b7aee61/pharmawuerz},
endnotereftype = {Journal Article},
interhash = {d2e035b969d177083cc87c5c9e339b7f},
intrahash = {943744138da616404cc303502b7aee61},
issn = {0022-3751 (Print) 0022-3751 (Linking)},
journal = {J Physiol},
keywords = {& *Lysophospholipids Acetylcholine/pharmacology Adenosine/pharmacology Agents/pharmacology Agonists/*pharmacology Animals Biotransformation/drug Cardiovascular Channels/drug Female GTP-Binding Guinea Heart/drug Male Membrane Muscarinic Myocardium/cytology/*metabolism Patch-Clamp Phospholipids/blood Pigs Potassium Potentials/drug Proteins/metabolism Signal Sphingosine/*analogs Techniques Transduction/drug derivatives/pharmacology effects effects/*metabolism effects/physiology},
month = {Dec 15},
note = {Bunemann, M Brandts, B zu Heringdorf, D M van Koppen, C J Jakobs,
K H Pott, L In Vitro Research Support, Non-U.S. Gov't England The
Journal of physiology J Physiol. 1995 Dec 15;489 ( Pt 3):701-7.},
pages = {701-7},
shorttitle = {Activation of muscarinic K+ current in guinea-pig atrial myocytes
by sphingosine-1-phosphate},
timestamp = {2010-12-14T18:12:06.000+0100},
title = {Activation of muscarinic K+ current in guinea-pig atrial myocytes
by sphingosine-1-phosphate},
url = {http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=8788935},
volume = {489 ( Pt 3)},
year = 1995
}