Linked Life Data

8384423

Source:http://linkedlifedata.com/resource/pubmed/id/8384423

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3 Pt 2
pubmed:dateCreated
1993-4-22
pubmed:abstractText
The present study investigated the influence of physical training on alterations leading to reduced adenosine 3',5'-cyclic monophosphate (cAMP) formation in aged myocardium. Senescent (28-mo-old) rats underwent a moderate treadmill exercise program and were compared with sedentary controls. In myocardial membranes from aged rats, isoprenaline-stimulated adenylate cyclase activity (AC) was reduced compared with that in young animals and was accompanied by an increase of pertussis toxin substrates (17.5%) and an increased amount of immunodetectable inhibitory guanine nucleotide-binding proteins (Gi alpha; 72%). Physical training reduced the amount of Gi alpha proteins (30-35%) in young and old animals and enhanced only isoprenaline-stimulated AC in the aged rats, and basal and 5'-guanylylimidodiphosphate [Gpp(NH)p]- as well as isoprenaline-stimulated AC in young rats. Physical training or aging had no effect on the number of beta-adrenoceptors or m-cholinoceptors or on forskolin-stimulated AC in either group. The amount of immunodetectable stimulatory guanine nucleotide-binding proteins (Gs alpha) using an antiserum raised against the COOH-terminal peptide of Gs alpha (RMHLRQYELL) was unchanged in either condition. It is concluded that enhanced Gi alpha expression might be one mechanism leading to depressed cAMP formation in aged myocardium. Depressed AC and increased Gi alpha can be partially reversed by physical training, especially in young myocardium. Gi alpha might serve as a regulator of cardiac AC in a variety of physiological and pathophysiological situations in the absence of beta-adrenoceptor changes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
264
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H805-14
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:8384423-Adenylate Cyclase, pubmed-meshheading:8384423-Adenylate Cyclase Toxin, pubmed-meshheading:8384423-Aging, pubmed-meshheading:8384423-Amino Acid Sequence, pubmed-meshheading:8384423-Animals, pubmed-meshheading:8384423-Cell Membrane, pubmed-meshheading:8384423-Cyclic AMP, pubmed-meshheading:8384423-GTP-Binding Proteins, pubmed-meshheading:8384423-Guanylyl Imidodiphosphate, pubmed-meshheading:8384423-Isoproterenol, pubmed-meshheading:8384423-Molecular Sequence Data, pubmed-meshheading:8384423-Myocardium, pubmed-meshheading:8384423-Pertussis Toxin, pubmed-meshheading:8384423-Physical Exertion, pubmed-meshheading:8384423-Rats, pubmed-meshheading:8384423-Rats, Sprague-Dawley, pubmed-meshheading:8384423-Receptors, Adrenergic, beta, pubmed-meshheading:8384423-Receptors, Cholinergic, pubmed-meshheading:8384423-Virulence Factors, Bordetella
pubmed:year
1993
pubmed:articleTitle
Effects of exercise on myocardial adenylate cyclase and Gi alpha expression in senescence.
pubmed:affiliation
Medizinische Klinik I, Klinikum Grosshadern, Universität Müchen, Munich, Germany.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't