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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
5 Pt 2
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pubmed:dateCreated |
1990-6-13
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pubmed:abstractText |
In normal heart, presynaptic cholinergic muscarinic and alpha 2-adrenergic mechanisms contribute to regional variations in the rate constant of norepinephrine turnover (kNE), an index of sympathetic neural function. To evaluate these mechanisms in the hypertrophied heart, pulmonary artery-constricted and sham-operated guinea pigs were pretreated with 1) saline vehicle (control) or 2) a combination of quinuclidinyl benzilate (Q), a muscarinic cholinergic antagonist, and yohimbine (Y), an alpha 2-adrenergic antagonist. An increase in kNE was determined in multiple regions of heart from incorporation of radiolabeled tyrosine into norepinephrine during a control period at 24 degrees C and again at 4 degrees C. In sham animals, kNE during cold stress was increased significantly (P less than 0.05) by Q + Y compared with vehicle, confirming that muscarinic cholinergic and/or alpha 2-adrenergic receptors exert a negative-feedback influence on sympathetic neurotransmitter synthesis. In pulmonary artery-constricted animals, in contrast, there were smaller increases in cardiac kNE compared with sham guinea pigs given Q + Y and subjected to cold stress. These data support the concept that muscarinic cholinergic and/or alpha 2-adrenergic presynaptic regulation of cardiac sympathetic function is altered in the hearts and vasculature of pulmonary artery-constricted guinea pigs.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
May
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pubmed:issn |
0002-9513
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
258
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
H1375-81
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pubmed:dateRevised |
2008-11-21
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pubmed:meshHeading |
pubmed-meshheading:2140019-Animals,
pubmed-meshheading:2140019-Blood Pressure,
pubmed-meshheading:2140019-Cardiomegaly,
pubmed-meshheading:2140019-Cold Temperature,
pubmed-meshheading:2140019-Constriction,
pubmed-meshheading:2140019-Guinea Pigs,
pubmed-meshheading:2140019-Male,
pubmed-meshheading:2140019-Myocardium,
pubmed-meshheading:2140019-Norepinephrine,
pubmed-meshheading:2140019-Pulmonary Artery,
pubmed-meshheading:2140019-Quinuclidinyl Benzilate,
pubmed-meshheading:2140019-Stress, Physiological,
pubmed-meshheading:2140019-Sympathetic Nervous System,
pubmed-meshheading:2140019-Synapses,
pubmed-meshheading:2140019-Temperature,
pubmed-meshheading:2140019-Yohimbine
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pubmed:year |
1990
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pubmed:articleTitle |
Ventricular hypertrophy and presynaptic regulation of sympathetic function.
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pubmed:affiliation |
Veterans Affairs Medical Center, Cardiovascular Center, Iowa City, Iowa.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, U.S. Gov't, Non-P.H.S.,
Research Support, Non-U.S. Gov't
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