Characterization of 5-hydroxytryptamine receptors in bovine coronary arteries.
This study was designed to determine the subtypes of 5-HT receptors present in bovine large coronary arteries and to characterize the response mediated by each subtype of receptor. Concentration-response relationships for 8-hydroxy-2-(di-n-propylamino)-tetralin (5-HT1A agonist) (0.3-100 microM), CGS-12066B maleate (5-HT1B agonist) (0.01-30 microM), alpha-methylserotonin maleate (5-HT2 agonist) (0.01-30 microM), 1-(m-chlorophenyl)-biguanide (5-HT3 agonist) (0.1-100 microM) and serotonin (0.1-300 microM) were studied in vitro using 2-mm segments of bovine proximal left anterior descending coronary artery. Each segmental ring was mounted in a 70-ml tissue bath for the measurement of isometric tension. 8-Hydroxy-2-(di-n-propylamino)-tetralin (10-100 microM), alpha-methylserotonin maleate (0.01-30 microM) and serotonin (0.1-300 microM) induced endothelium-independent contraction, whereas CGS-12066B maleate and 1-(m-chlorophenyl)-biguanide had no effect in this species. Contractions induced by 8-hydroxy-2-(di-n-propylamino)-tetralin or alpha-methylserotonin maleate were attenuated by pretreatment with S(-)propranolol (2.6 microM), a relatively selective 5-HT1A and 5-HT1B receptor antagonist, and ketanserin (0.3 microM), a selective 5-HT2 receptor antagonist, respectively. Pretreatment with S(-)propranolol or ketanserin also attenuated serotonin-induced contraction, demonstrating that serotonin mediates contraction through both 5-HT1A and 5-HT2 receptors in bovine large coronary arteries.
Foy
R A
RA
Department of Pharmacology, Medical College of Ohio, Toledo.
Myles
J L
JL
Wilkerson
R D
RD
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D002417:Cattle; D004305:Dose-Response Relationship, Drug; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism; D009569:Nitric Oxide / Q000494:pharmacology; D011985:Receptors, Serotonin / Q000145:classification / Q000187:drug effects*; D012701:Serotonin / Q000031:analogs & derivatives* / Q000494:pharmacology; D012702:Serotonin Antagonists / Q000494:pharmacology; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*
D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; D013764:Tetrahydronaphthalenes; C042390:alpha-methylserotonin; D009569:Nitric Oxide; D012701:Serotonin; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin