Publication Date:
1987-11-27
Description:
A possible direct effect of guanine nucleotide binding (G) proteins on calcium channels was examined in membrane patches excised from guinea pig cardiac myocytes and bovine cardiac sarcolemmal vesicles incorporated into planar lipid bilayers. The guanosine triphosphate analog, GTP gamma S, prolonged the survival of excised calcium channels independently of the presence of adenosine 3',5'-monophosphate (cAMP), adenosine triphosphate, cAMP-activated protein kinase, and the protein kinase C activator tetradecanoyl phorbol acetate. A specific G protein, activated Gs, or its alpha subunit, purified from the plasma membranes of human erythrocytes, prolonged the survival of excised channels and stimulated the activity of incorporated channels. Thus, in addition to regulating calcium channels indirectly through activation of cytoplasmic kinases, G proteins can regulate calcium channels directly. Since they also directly regulate a subset of potassium channels, G proteins are now known to directly gate two classes of membrane ion channels.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Yatani, A -- Codina, J -- Imoto, Y -- Reeves, J P -- Birnbaumer, L -- Brown, A M -- HL-31154/HL/NHLBI NIH HHS/ -- HL-36930/HL/NHLBI NIH HHS/ -- HL-37044/HL/NHLBI NIH HHS/ -- New York, N.Y. -- Science. 1987 Nov 27;238(4831):1288-92.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Physiology and Molecular Biophysics, Baylor College of Medicine, Houston, TX 77030.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/2446390" target="_blank"〉PubMed〈/a〉
Keywords:
3-Pyridinecarboxylic acid,
;
1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl
;
ester/pharmacology
;
Animals
;
Calcium/metabolism
;
Colforsin/pharmacology
;
GTP-Binding Proteins/*physiology
;
Guanosine 5'-O-(3-Thiotriphosphate)
;
Guanosine Triphosphate/analogs & derivatives/pharmacology
;
Guinea Pigs
;
Heart/*physiology
;
Ion Channels/drug effects/*physiology
;
Isoproterenol/pharmacology
;
Leupeptins/pharmacology
;
Membrane Potentials/drug effects
;
Phosphorylation
;
Thionucleotides/pharmacology
;
Ventricular Function
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
