title: Action of vasodilator agents on inner and outer muscle of bovine coronary arteries.
abstract: Noradrenaline and adrenaline (via beta-receptors), adenosine, and prostacyclin all relaxed inner more than outer muscle in coronary arteries contracted by histamine. In submaximal concentrations, noradrenaline, and usually the other dilator hormones, produced proportionately even greater relaxation of inner than outer muscle. Inner and outer strips contracted by 5-hydroxytryptamine showed similar but smaller differences in response to noradrenaline. Outer strips contracted by methacholine were little affected by noradrenaline, though inorganic nitrite relaxed them.
mesh_terms: D000241:Adenosine / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D003331:Coronary Vessels / Q000187:drug effects*; D004837:Epinephrine / Q000494:pharmacology; D011464:Epoprostenol / Q000494:pharmacology; D006632:Histamine / Q000494:pharmacology; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009638:Norepinephrine / Q000494:pharmacology; D012977:Sodium Nitrite / Q000494:pharmacology; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: D014665:Vasodilator Agents; D006632:Histamine; D011464:Epoprostenol; D000241:Adenosine; D012977:Sodium Nitrite; D009638:Norepinephrine; D004837:Epinephrine