Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2002-1-30
pubmed:abstractText
In rats, injection of monocrotaline (MCT) causes pulmonary hypertension that leads to right ventricular failure. The aim of the present study was to characterize the responses of various vessels (the pulmonary artery, the thoracic aorta and small mesenteric arteries) to noradrenaline (NA; 10(-10)-10(-5) M) and carbachol (10 microM) in MCT-treated rats. For this purpose 6-week-old male Wistar rats ( n=13) were treated with 60 mg/kg MCT i.p. After 4-6 weeks the rats were killed and the heart, lungs and vessels removed and compared with those from age-matched saline-treated control rats ( n=47). First, the alpha(1)-adrenoceptor subtype(s) involved in the vascular NA-responses were characterized in normal rats using the alpha(1)-adrenoceptor subtype-selective antagonists 5-methylurapidil (5-MU; competitive alpha(1A)-adrenoceptor antagonist; 10(-8)-10(-6) M), BMY 7378 (competitive alpha(1D)-adrenoceptor antagonist; 10(-7)-10(-6) M) and chloroethylclonidine (CEC; irreversible alpha(1B)-adrenoceptor antagonist; 30 microM). In the pulmonary artery the pA(2) for BMY 7378 was 7.93, while that for 5-MU could not be calculated. CEC suppressed the NA-induced contraction significantly. In the thoracic aorta, the pA(2) for BMY 7378 was 8.06, while 5-MU was less effective (pA(2) 7.31). CEC again suppressed the NA-induced contraction significantly. In mesenteric arteries, CEC was ineffective whereas 5-MU induced a significant, rightwards shift of the concentration/response curve for NA (pA(2) 8.05). BMY 7378 had a lower pA(2) (6.6). MCT-treated rats developed an increased right ventricular pressure, obliteration of pulmonary vessels and inflammatory lung infiltration. In the pulmonary artery, but not in the thoracic aorta or mesenteric artery of MCT-treated rats NA-induced contraction was attenuated. In addition, carbachol-induced relaxation was reduced in the pulmonary and mesenteric arteries. In conclusion, NA-induced contraction is mediated predominantly by alpha(1A)-adrenoceptors in small mesenteric arteries, by alpha(1D)-adrenoceptors in the thoracic aorta (with a contribution from alpha(1A)- and alpha(1B)-adrenoceptors) and by alpha(1D)- and alpha(1B)-adrenoceptors in pulmonary arteries. MCT leads to reduced NA-responsiveness exclusively in the pulmonary artery that does not, however, account for the development of pulmonary hypertension, and to a more generalized endothelial dysfunction which may contribute to the pathogenesis of pulmonary hypertension in this model.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/5-methylurapidil, http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic alpha-1 Receptor Agonists, http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic alpha-1 Receptor..., http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic alpha-Agonists, http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic alpha-Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/BMY 7378, http://linkedlifedata.com/resource/pubmed/chemical/Clonidine, http://linkedlifedata.com/resource/pubmed/chemical/Monocrotaline, http://linkedlifedata.com/resource/pubmed/chemical/Norepinephrine, http://linkedlifedata.com/resource/pubmed/chemical/Piperazines, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Adrenergic, alpha-1, http://linkedlifedata.com/resource/pubmed/chemical/chlorethylclonidine
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0028-1298
pubmed:author
pubmed:issnType
Print
pubmed:volume
365
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
87-95
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed-meshheading:11819025-Adrenergic alpha-1 Receptor Agonists, pubmed-meshheading:11819025-Adrenergic alpha-1 Receptor Antagonists, pubmed-meshheading:11819025-Adrenergic alpha-Agonists, pubmed-meshheading:11819025-Adrenergic alpha-Antagonists, pubmed-meshheading:11819025-Animals, pubmed-meshheading:11819025-Clonidine, pubmed-meshheading:11819025-Hypertension, Pulmonary, pubmed-meshheading:11819025-Hypertrophy, Right Ventricular, pubmed-meshheading:11819025-Male, pubmed-meshheading:11819025-Mesenteric Arteries, pubmed-meshheading:11819025-Monocrotaline, pubmed-meshheading:11819025-Norepinephrine, pubmed-meshheading:11819025-Piperazines, pubmed-meshheading:11819025-Pulmonary Artery, pubmed-meshheading:11819025-Rats, pubmed-meshheading:11819025-Rats, Wistar, pubmed-meshheading:11819025-Receptors, Adrenergic, alpha-1, pubmed-meshheading:11819025-Thoracic Arteries, pubmed-meshheading:11819025-Vasoconstriction
pubmed:year
2002
pubmed:articleTitle
Changes in alpha(1)-adrenergic vascular reactivity in monocrotaline-treated rats.
pubmed:affiliation
Institute of Pharmacology, University of Halle-Wittenberg, Magdeburger Strasse 4, 06097 Halle/Saale, Germany. stefan.dhein@medizin.uni-halle.de
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't