Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1991-6-19
pubmed:abstractText
The hypothesis that adenosine mediates blood flow increments in contracting skeletal muscle was evaluated by intravital microscopy of the microcirculation in the tenuissimus muscle of anesthetized rabbits. Motor nerve stimulation elicited muscle contractions and frequency-dependent arteriolar dilatation, particularly in terminal arterioles. The pulse duration (0.05 ms) and voltage (1.5-5 V) precluded activation of vasoconstrictor fibers, as also indicated by the lack of effect of phentolamine on resting vascular tone and on the hyperemic response to nerve stimulation. The specific adenosine receptor antagonist, 1,3-dipropyl-8-p-sulfo-phenylxanthine (DPSPX; 10(-5) M), attenuated the hyperemic response to muscle contractions. The adenosine uptake inhibitor dipyridamole (10(-8)-10(-6) M) dose-dependently dilated microvessels, an effect prevented by DPSPX (10(-5) M). Moreover, dipyridamole (10(-7) M) augmented contraction-induced hyperemia. The enhancement by dipyridamole was reversed by DPSPX (10(-5) M). The effects of adenosine uptake inhibitor and antagonist were invariably more marked in terminal than in transverse arterioles, and also more pronounced at higher stimulation frequencies. Motor nerve stimulation failed to induce alterations in vascular diameters when the neuromuscular junction was blocked by pancuronium. Thus, our observations indicate that functional hyperemia after motor nerve-induced contractions of the skeletal muscle was of postjunctional origin. Apparently, activation of adenosine receptors was responsible for a part of the evoked vasodilation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0028-1298
pubmed:author
pubmed:issnType
Print
pubmed:volume
343
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
52-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Role of adenosine in functional hyperemia in skeletal muscle as indicated by pharmacological tools.
pubmed:affiliation
Department of Physiology, Karolinska Institutet, Stockholm, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't