Linked Life Data

15249169

Source:http://linkedlifedata.com/resource/pubmed/id/15249169

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
2004-7-13
pubmed:abstractText
To determine the effect of a completely developed reperfused myocardial infarction model on beta-adrenoceptor responsiveness, we induced a 90-min regional ischemia followed by 72 h of reperfusion in dog hearts. Regional myocardial blood flow was determined after 60 min of ischemia using radioactive microspheres. beta-adrenoceptor density was reduced in the ischemic endocardium (95+/-16 fmol/mg) and epicardium (160+/-13 fmol/mg) compared to the nonischemic region (304+/-21 fmol/mg). beta-adrenoceptor density in the ischemic endocardium varied with the degree of collateral blood flow measured (r2=0.79, P<0.05); this relation was the opposite of that in the ischemic epicardium (r2=0.77, P<0.05). Higher levels of tissue catecholamines and G protein-coupled receptor kinase 2 (GRK2) were observed in the ischemic epicardium as compared to nonischemic tissue. Forskolin-induced adenylyl cyclase activities were depressed in both ischemic regions as compared to nonischemic region, correlating with a reduction in regional myocardial blood flow. Using forskolin stimulation as covariate, no difference in isoproterenol-induced adenylyl cyclase activity was identified in the different regions. It is concluded that cAMP production induced by beta-adrenoceptor activation is dependent upon adenylyl cyclase enzyme activity rather than beta-adrenoceptor density in the ischemic myocardium. However, the density of the beta-adrenoceptor in the viable ischemic regions can be modified by the presence of GRK2 and tissue catecholamines, an index of regional sympathetic efferent postganglionic nerve terminal activity.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0014-2999
pubmed:author
pubmed:issnType
Print
pubmed:day
14
pubmed:volume
495
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
185-91
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:15249169-Adenylate Cyclase, pubmed-meshheading:15249169-Adrenergic beta-Agonists, pubmed-meshheading:15249169-Animals, pubmed-meshheading:15249169-Body Temperature, pubmed-meshheading:15249169-Catecholamines, pubmed-meshheading:15249169-Coronary Circulation, pubmed-meshheading:15249169-Cyclic AMP, pubmed-meshheading:15249169-Cyclic AMP-Dependent Protein Kinases, pubmed-meshheading:15249169-Dogs, pubmed-meshheading:15249169-Female, pubmed-meshheading:15249169-Forskolin, pubmed-meshheading:15249169-Hematocrit, pubmed-meshheading:15249169-Hemodynamics, pubmed-meshheading:15249169-Hemoglobins, pubmed-meshheading:15249169-Isoproterenol, pubmed-meshheading:15249169-Leukocyte Count, pubmed-meshheading:15249169-Male, pubmed-meshheading:15249169-Myocardial Reperfusion Injury, pubmed-meshheading:15249169-Myocardium, pubmed-meshheading:15249169-Pericardium, pubmed-meshheading:15249169-Receptors, Adrenergic, beta, pubmed-meshheading:15249169-Time Factors, pubmed-meshheading:15249169-beta-Adrenergic Receptor Kinases
pubmed:year
2004
pubmed:articleTitle
Alterations of beta-adrenoceptor responsiveness in postischemic myocardium after 72 h of reperfusion.
pubmed:affiliation
Département de Pharmacologie, Groupe de Recherche sur le Système Nerveux Autonome, Faculté de Médecine, Université de Montréal, and Centre de Biomédecine, Hôpital du Sacré-Coeur de Montréal, 5400 boul. Gouin Ouest, Montréal, Québec, Canada H4J 1C5.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't