Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
4
|
pubmed:dateCreated |
1995-9-5
|
pubmed:abstractText |
In guinea pig main pulmonary artery precontracted with noradrenaline, adenosine exerted an initial phasic contraction followed by a tonic contraction and a slow relaxation. After selective blockade by 1,3-dipropyl-8-cyclopentylxanthine (DPCPX: 10 nM) of A1 receptors, adenosine only elicited a rapid relaxation. This initial response was characterized by use of adenosine (AR) and its analogues N6-cyclopentyl-adenosine (CPA), R-N6-phenylisopropyladenosine (R-PIA), 2-chloroadenosine (CADO), 5'-N-ethyl-carboxamidoadenosine(NECA), N6-2-(4-aminophenyl) ethyl adenosine (APNEA) and 2-p-((carboxyethyl)-phenethylamino)-5'-carboxamidoadenosine (CGS 21 680). The order of potency of the adenosine analogues for purine-induced phasic contraction was CPA > R-PIA > NECA = APNEA > AR > CGS 21 680 suggesting the involvement of activation of A1 type adenosine receptors in the contraction phase. DPCPX antagonized the CPA-induced contraction with a pA2 = 9.27 +/- 0.26, but the Schild plot slope parameter was significantly lower than unity (0.58 +/- 0.09). In contrast, in electrically driven guinea pig atrial myocardium (a tissue reported to possess A1 receptors), the DPCPX-CPA antagonism was purely competitive (pA2 = 8.95 +/- 0.06; slope = 0.93 +/- 0.06). In the presence of 300 nM DPCPX, the rank order of potency for the purine-induced fast relaxation was NECA > CADO = AR > CGS 21 680 = R-PIA > CPA. The NECA- and adenosine-induced relaxation was influenced neither by 300 nM CP 66713 (an antagonist at A2a receptors), nor by endothelial removal and inhibition of nitric oxide synthase (100 microM NG-nitro-L-arginine: L-NOARG).(ABSTRACT TRUNCATED AT 250 WORDS)
|
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Adenosine,
http://linkedlifedata.com/resource/pubmed/chemical/Amino Acid Oxidoreductases,
http://linkedlifedata.com/resource/pubmed/chemical/Nitric Oxide Synthase,
http://linkedlifedata.com/resource/pubmed/chemical/Purinergic P1 Receptor Antagonists,
http://linkedlifedata.com/resource/pubmed/chemical/Purines,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Purinergic P1
|
pubmed:status |
MEDLINE
|
pubmed:month |
Apr
|
pubmed:issn |
0028-1298
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:volume |
351
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
417-25
|
pubmed:dateRevised |
2010-11-18
|
pubmed:meshHeading |
pubmed-meshheading:7543187-Adenosine,
pubmed-meshheading:7543187-Amino Acid Oxidoreductases,
pubmed-meshheading:7543187-Animals,
pubmed-meshheading:7543187-Guinea Pigs,
pubmed-meshheading:7543187-Isometric Contraction,
pubmed-meshheading:7543187-Muscle, Smooth, Vascular,
pubmed-meshheading:7543187-Muscle Contraction,
pubmed-meshheading:7543187-Muscle Relaxation,
pubmed-meshheading:7543187-Myocardial Contraction,
pubmed-meshheading:7543187-Nitric Oxide Synthase,
pubmed-meshheading:7543187-Pulmonary Artery,
pubmed-meshheading:7543187-Purinergic P1 Receptor Antagonists,
pubmed-meshheading:7543187-Purines,
pubmed-meshheading:7543187-Receptors, Purinergic P1
|
pubmed:year |
1995
|
pubmed:articleTitle |
Adenosine receptors mediate both contractile and relaxant effects of adenosine in main pulmonary artery of guinea pigs.
|
pubmed:affiliation |
Department of Pharmacology, University, Medical School of Debrecen, Hungary.
|
pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, Non-U.S. Gov't
|