Linked Life Data

12063280

Source:http://linkedlifedata.com/resource/pubmed/id/12063280

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-6-13
pubmed:abstractText
The conduction of vasodilation along resistance vessels has been presumed to reflect the electrotonic spread of hyperpolarization from cell to cell along the vessel wall through gap junction channels. However, the vasomotor response to acetylcholine (ACh) encompasses greater distances than can be explained by passive decay. To investigate the underlying mechanism for this behavior, we tested the hypothesis that ACh augments the conduction of hyperpolarization. Feed arteries (n = 23; diameter, 58 +/- 4 microm; segment length, 2-8 mm) were isolated from the hamster retractor muscle, cannulated at each end, and pressurized to 75 mmHg (at 37 degrees C). Vessels were impaled with one or two dye-containing microelectrodes simultaneously (separation distance, 50 microm to 3.5 mm). Membrane potential (E(m)) (rest, approximately -30 mV) and electrical responses were similar between endothelium and smooth muscle, as predicted for robust myoendothelial coupling. Current injection (-0.8 nA, 1.5 s) evoked hyperpolarization (-10 +/- 1 mV; membrane time constant, 240 ms) that conducted along the vessel with a length constant (lambda) = 1.2 +/- 0.1 mm; spontaneous E(m) oscillations (approximately 1 Hz) decayed with lambda = 1.2 + 0.1 mm. In contrast, ACh microiontophoresis (500 nA, 500 ms, 1 microm tip) evoked hyperpolarization (-14 +/- 2 mV) that conducted with lambda = 1.9 +/- 0.1 mm, 60% further (P < 0.05) than responses evoked by purely electrical stimuli. These findings indicate that ACh augments the conduction of hyperpolarization along the vessel wall.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0363-6135
pubmed:author
pubmed:issnType
Print
pubmed:volume
283
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H102-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Conduction of hyperpolarization along hamster feed arteries: augmentation by acetylcholine.
pubmed:affiliation
The John B. Pierce Laboratory and Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut 06519, USA.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.