Linked Life Data

15681710

Source:http://linkedlifedata.com/resource/pubmed/id/15681710

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2005-5-17
pubmed:abstractText
Adequate growth of coronary vasculature in the remaining left ventricular (LV) myocardium after myocardial infarction (post-MI) is a crucial factor for myocyte survival and performance. We previously demonstrated that post-MI coronary angiogenesis can be stimulated by bradycardia induced with the ATP-sensitive K(+) channel antagonist alinidine. In this study, we tested the hypothesis that heart rate reduction with beta-blockade may also induce coronary growth in the post-MI heart. Transmural MI was induced in 12-mo-old male Sprague-Dawley rats by occlusion of the left anterior descending coronary artery. Bradycardia was induced by administration of the beta-adrenoceptor blocker atenolol (AT) via drinking water (30 mg/day). Three groups of rats were compared: 1) control/sham (C/SH), 2) MI, and 3) MI + AT. In the MI + AT rats, heart rate was consistently reduced by 25-28% compared with C/SH rats. At 4 wk after left anterior descending coronary ligation, infarct size was similar in MI and MI + AT rats (67.1 and 61.5%, respectively), whereas a greater ventricular hypertrophy occurred in bradycardic rats, as indicated by a higher ventricular weight-to-body weight ratio (3.4 +/- 0.1 vs. 2.8 +/- 0.1 mg/g in MI rats). Analysis of LV function revealed a smaller drop in ejection fraction in the MI + AT than in the MI group ( approximately 24 vs. approximately 35%). Furthermore, in MI + AT rats, maximal coronary conductance and coronary perfusion reserve were significantly improved compared with the MI group. The better myocardial perfusion indexes in MI + AT rats were associated with a greater increase in arteriolar length density than in the MI group. Thus chronic reduction of heart rate induced with beta-selective blockade promotes growth of coronary arterioles and, thereby, facilitates regional myocardial perfusion in post-MI hearts.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0363-6135
pubmed:author
pubmed:issnType
Print
pubmed:volume
288
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H2684-93
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Reduction of heart rate by chronic beta1-adrenoceptor blockade promotes growth of arterioles and preserves coronary perfusion reserve in postinfarcted heart.
pubmed:affiliation
Dept. of Anatomy and Cell Biology, Carver College of Medicine, 1-402 Bowen Science Bldg., Univ. of Iowa, Iowa City, IA 52242, USA. eduard-dedkov@uiowa.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, N.I.H., Extramural