Linked Life Data

3202193

Source:http://linkedlifedata.com/resource/pubmed/id/3202193

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6 Pt 2
pubmed:dateCreated
1989-1-26
pubmed:abstractText
The effects of sublethal endotoxemia on the regulation of coronary flow by myocardial metabolism were examined in the isolated perfused heart preparation. Fasted Sprague-Dawley rats were injected (ip) with either endotoxin (0.5 mg/kg of body wt) or 5% dextrose 12 h before heart perfusion. The efficacy of endotoxin treatment was determined by measurement of plasma [NH3] and [urea] and colonic temperature. During perfusion with buffer containing glucose-pyruvate, oxygen consumption and coronary flow were increased by 17 and 42%, respectively, in hearts from endotoxin-treated rats as compared with those from controls. In the hearts from endotoxemic animals, the mitochondrial [NAD+]/[NADH] was decreased by approximately 25%, and the active form of pyruvate dehydrogenase was increased by 36% as compared with control hearts. [ATP]f/[ADP]f[Pi] was unaltered. The enhanced metabolic rate was associated with comparable changes in peak systolic pressure development, maximal positive and negative dP/dt, and the tension-time index when measured in the isovolumetric preparation. In these hearts, stimulation of respiration by perfusion with an alternate source of fuel or inhibition by infusion of amytal elicited large, transient increases in the level of coronary flow that returned rapidly to prestimulus values. By contrast, in hearts from controls, the transient increase in flow was coupled to sustained vasodilation, i.e., approximately 30% rise in flow for either metabolic condition. In both groups, [ATP]f/[ADP]f[Pi] either increased or decreased with stimulation or inhibition of respiration, respectively. Adenosine (1.2 microM) produced a 35% increase in flow in the hearts from the control animals, whereas it was without significant effect in those from the endotoxin-treated animals. It is concluded that sublethal endotoxemia causes 1) an increased metabolic rate and enhanced mechanical activity in the heart and 2) an uncoupling of flow from regulation by cardiac metabolism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
255
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1295-304
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Myocardial metabolism and coronary flow: effects of endotoxemia.
pubmed:affiliation
Department of Biochemistry, University of Pennsylvania School of Medicine, Philadelphia 19104.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't