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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
2
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pubmed:dateCreated |
1989-3-27
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pubmed:abstractText |
The possible occurrence of non-adrenergic mechanisms in the sympathetic vascular control of the nasal mucosa was studied in vivo using reserpine-treated pigs (1 mg kg-1, i.v., 24 h earlier) in combination with pharmacological blockade of alpha-adrenoceptors by local phenoxybenzamine (1 mg kg-1, i.a.) infusion. The nasal mucosal depletion (99%) of the content of noradrenaline (NA) in reserpinized animals was not influenced by preganglionic denervation while the depletion (44%) of neuropeptide Y (NPY) was prevented. Upon stimulation with single shocks, 25% of the arterial blood flow reduction and 47% of the nasal mucosal volume reduction (reflecting contraction of venous sinusoids) were still present after reserpine as compared with controls. In reserpinized animals, the vascular responses were slow developing and long-lasting, and about 60% remained at 0.59 Hz and more than 80% at 6.9 Hz. The vascular effects after reserpine were, however, subjected to fatigue, which may explain why phenoxybenzamine treatment still reduced the functional effects in the absence of NA. Local intra-arterial injections of NA, NPY and the metabolically stable adenosine-5'-triphosphate analogue alpha, beta-methylene ATP (mATP) caused reduction in both arterial blood flow and nasal mucosal volume. The C-terminal fragment of NPY (NPY 13-36) also induced nasal vasoconstriction although with a fivefold lower potency than NPY 1-36. Adenosine-5'-triphosphate caused a biphasic vascular effect with vasodilatatory actions at low doses and a short-lasting vasoconstriction followed by vasodilatation at very high doses (100-fold higher than the threshold response to mATP). In contrast to the response to NA, the long-lasting vascular effects of NPY and mATP were resistant to phenoxybenzamine treatment. In conclusion, although NA is likely to mediate most of the sympathetic vascular responses to low-frequency stimulation in the pig nasal mucosa, a large resistance and capacitance vessel component upon high-frequency stimulation seems to be non-adrenergic and mimicked by NPY rather than ATP.
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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 |
Jun
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pubmed:issn |
0001-6772
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
133
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
183-97
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:3227914-Adenosine Triphosphate,
pubmed-meshheading:3227914-Administration, Intranasal,
pubmed-meshheading:3227914-Animals,
pubmed-meshheading:3227914-Electric Stimulation,
pubmed-meshheading:3227914-Ganglia, Sympathetic,
pubmed-meshheading:3227914-Injections, Intra-Arterial,
pubmed-meshheading:3227914-Nasal Mucosa,
pubmed-meshheading:3227914-Neuropeptide Y,
pubmed-meshheading:3227914-Reserpine,
pubmed-meshheading:3227914-Swine,
pubmed-meshheading:3227914-Vasoconstriction,
pubmed-meshheading:3227914-Vasodilation
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pubmed:year |
1988
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pubmed:articleTitle |
Sympathetic vascular control of the pig nasal mucosa (2): Reserpine-resistant, non-adrenergic nervous responses in relation to neuropeptide Y and ATP.
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pubmed:affiliation |
Department of Pharmacology, Karolinska Institutet, Stockholm, Sweden.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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