Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
24
|
pubmed:dateCreated |
1989-2-16
|
pubmed:abstractText |
The differential effects of alpha 2-adrenoceptor stimulation on myocardial contractility and coronary circulation were examined in the isolated perfused rat heart. We studied 20 Sprague-Dawley rats of similar age (26-28 weeks) and body weight (500-550 gm). Myocardial contractility (LV +dp/dt and developed pressure, LVP) and coronary flow resistance (CFR) were tested in the isolated isovolumic hearts using Langendorff preparation at a constant perfusion rate (2.5 ml/min/100 g BW) of Krebs-Henseleit bicarbonate solution. Group I (N-7) received B-HT 920 (specific alpha 2-adrenergic agonist, 0.6 to 58 micrograms/min), Group II (N-7) received B-HT 920+Yohimbine (300 nM in the perfusate). Group III (N-6) received vehicle only. Baseline LVP, LV +dP/dt and CFR were not significantly different among the 3 groups. During drug or vehicle administration, LVP and LV +dP/dt remained unchanged in all the groups. Coronary flow resistance increased in a dose-response fashion with a maximum increase of 22.7 +/- 3.6 (SE) mmHg/ml/min/g LV in Group I, and 10.5 +/- 2.0 mmHg/ml/min/g LV in Group II (p less than 0.02). We conclude that in the Sprague-Dawley rat heart, the physiologic effects of alpha 2-adrenoceptors are predominant in the coronary circulation but not in the myocardium itself possibly because of absence of post-synaptic alpha 2-adrenergic receptors in the rat myocardium.
|
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic alpha-Agonists,
http://linkedlifedata.com/resource/pubmed/chemical/Azepines,
http://linkedlifedata.com/resource/pubmed/chemical/Isoproterenol,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Adrenergic, alpha,
http://linkedlifedata.com/resource/pubmed/chemical/Yohimbine,
http://linkedlifedata.com/resource/pubmed/chemical/talipexole
|
pubmed:status |
MEDLINE
|
pubmed:issn |
0024-3205
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:volume |
43
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
2025-33
|
pubmed:dateRevised |
2006-11-15
|
pubmed:meshHeading |
pubmed-meshheading:2905407-Adrenergic alpha-Agonists,
pubmed-meshheading:2905407-Animals,
pubmed-meshheading:2905407-Azepines,
pubmed-meshheading:2905407-Blood Pressure,
pubmed-meshheading:2905407-Coronary Circulation,
pubmed-meshheading:2905407-Coronary Vessels,
pubmed-meshheading:2905407-Heart,
pubmed-meshheading:2905407-Isoproterenol,
pubmed-meshheading:2905407-Male,
pubmed-meshheading:2905407-Muscle, Smooth, Vascular,
pubmed-meshheading:2905407-Myocardial Contraction,
pubmed-meshheading:2905407-Rats,
pubmed-meshheading:2905407-Receptors, Adrenergic, alpha,
pubmed-meshheading:2905407-Vascular Resistance,
pubmed-meshheading:2905407-Yohimbine
|
pubmed:year |
1988
|
pubmed:articleTitle |
The differential effects of alpha 2-adrenergic stimulation on the myocardium and coronary vessels in the isolated rat heart.
|
pubmed:affiliation |
Department of Heart and Hypertension Research, Cleveland Clinic Foundation, Ohio.
|
pubmed:publicationType |
Journal Article,
In Vitro
|