Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3 Pt 2
pubmed:dateCreated
1990-4-23
pubmed:abstractText
This study was designed to determine whether cardiac vagal afferents exert an inhibitory influence on increases in regional vascular resistance during exercise and to determine whether endurance exercise training enhances the inhibitory influence of cardiac vagal afferents. We measured changes in regional vascular resistance in 12 rabbits at rest and during running at 12.6 m/min, 20% grade, before and after reversible denervation of cardiac afferents (intrapericardial procainamide HCl, 2%). In addition, these procedures were repeated in five of these rabbits following an 8-wk endurance exercise training program. Because intrapericardial injections of procainamide anesthetize both the efferent as well as the afferent innervation to the heart, it was necessary to determine the effects of blocking the efferent innervation on the regulation of regional vascular resistance during exercise. Rabbits were instrumented with Doppler ultrasonic flow probes around the renal (R), mesenteric (M), ascending, and terminal aortic (TA) arteries. Catheters were positioned in the central ear artery and vein and pericardial sac. Mean arterial pressure, heart rate, cardiac output, R, M, TA, and systemic (S) resistances were determined. Exercise changed R (+37 +/- 4%), M (+88 +/- 9%), TA (-62 +/- 6%), and S (-34 +/- 3) resistances. Subsequent cardiac efferent blockade alone had no significant effect on regional vascular resistance during exercise. Combined efferent and afferent blockade resulted in significant increases in R (+62 +/- 6%) and M resistance (+134 +/- 13%) but did not alter TA (-51 +/- 4%) or S (-27 +/- 2%) resistance during exercise. Exercise training significantly enhanced the inhibitory influence of cardiac afferents on R and M regional vascular resistance.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
258
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H842-7
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Regional vascular resistance during exercise: role of cardiac afferents and exercise training.
pubmed:affiliation
Department of Pharmacology, University of Texas Health Science Center, San Antonio 78284-7764.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.