Biomaterial Database

Characteristics of canine coronary resistance arteries: importance of endothelium. 1989

P R Myers, and P F Banitt, and R Guerra, and D G Harrison

Department of Internal Medicine, University of Iowa College of Medicine, Iowa City.

Canine coronary resistance vessels were studied in vitro to examine the role of the endothelium in modulating responses to acetylcholine, vasopressin, and thrombin and to compare these responses to those found in large epicardial vessels. Acetylcholine had no effect on passively distended microvessels; however, after preconstriction with the thromboxane analogue, U 46619 caused dose-dependent vasodilation [50% effective concentration (EC50), 0.05 microM; maximum response, 97.9 +/- 2.1% relaxation]. Large epicardial arterial rings studied in organ chambers similarly relaxed to acetylcholine (EC50, 0.07 microM; maximum response, 79 +/- 5% relaxation). Hemoglobin was utilized to inactivate endothelium-derived relaxing factor (EDRF), resulting in reversal of acetylcholine vasodilation in both the microvessels (92 +/- 3.2% reversal) and the large epicardial vessels (117 +/- 9%). Hemoglobin had no effect on passively distended or preconstricted microvessels. Vasopressin constricted resistance vessels by 22.3 +/- 5.9 microns at 500 microU/ml. Hemoglobin potentiated this response by 100%, suggesting that vasopressin elicited EDRF release. In large coronary arteries, however, vasopressin elicited endothelium-dependent dilation with maximal relaxation of 36 +/- 9% at 3,000 microU/ml. Thrombin produced endothelium-dependent relaxation of large epicardial arterial rings but only constricted coronary microvessels. The response to thrombin was not altered by hemoglobin. This study demonstrates that the endothelium of coronary microvessels, like that of larger vessels, importantly modulates vascular reactivity to selected agents. Furthermore, major differences exist between large and small coronary arteries in their response to vasopressin and thrombin.

UI	MeSH Term	Description	Entries
D007213	Indomethacin	A non-steroidal anti-inflammatory agent (NSAID) that inhibits CYCLOOXYGENASE, which is necessary for the formation of PROSTAGLANDINS and other AUTACOIDS. It also inhibits the motility of POLYMORPHONUCLEAR LEUKOCYTES.	Amuno,Indocid,Indocin,Indomet 140,Indometacin,Indomethacin Hydrochloride,Metindol,Osmosin
D008297	Male		Males
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009131	Muscle, Smooth, Vascular	The nonstriated involuntary muscle tissue of blood vessels.	Vascular Smooth Muscle,Muscle, Vascular Smooth,Muscles, Vascular Smooth,Smooth Muscle, Vascular,Smooth Muscles, Vascular,Vascular Smooth Muscles
D009569	Nitric Oxide	A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.	Endogenous Nitrate Vasodilator,Mononitrogen Monoxide,Nitric Oxide, Endothelium-Derived,Nitrogen Monoxide,Endothelium-Derived Nitric Oxide,Monoxide, Mononitrogen,Monoxide, Nitrogen,Nitrate Vasodilator, Endogenous,Nitric Oxide, Endothelium Derived,Oxide, Nitric,Vasodilator, Endogenous Nitrate
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D011450	Prostaglandin Endoperoxides, Synthetic	Synthetic compounds that are analogs of the naturally occurring prostaglandin endoperoxides and that mimic their pharmacologic and physiologic activities. They are usually more stable than the naturally occurring compounds.	Prostaglandin Endoperoxide Analogs,Prostaglandin Endoperoxide Analogues,Synthetic Prostaglandin Endoperoxides,Analogues, Prostaglandin Endoperoxide,Endoperoxide Analogues, Prostaglandin,Endoperoxides, Synthetic Prostaglandin
D011796	Quinacrine	An acridine derivative formerly widely used as an antimalarial but superseded by chloroquine in recent years. It has also been used as an anthelmintic and in the treatment of giardiasis and malignant effusions. It is used in cell biological experiments as an inhibitor of phospholipase A2.	Mepacrine,Acrichine,Atabrine,Atebrin,Quinacrine Dihydrochloride,Quinacrine Dihydrochloride, Dihydrate,Quinacrine Dihyrochloride, (R)-Isomer,Quinacrine Dihyrochloride, (S)-Isomer,Quinacrine Dimesylate,Quinacrine Hydrochloride,Quinacrine Monoacetate,Quinacrine Monohydrochloride,Quinacrine Monomesylate,Quinacrine, (+-)-Isomer,Quinacrine, (R)-Isomer,Quinacrine, (S)-Isomer,Dihydrochloride, Quinacrine,Dimesylate, Quinacrine,Hydrochloride, Quinacrine,Monoacetate, Quinacrine,Monohydrochloride, Quinacrine,Monomesylate, Quinacrine
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D003331	Coronary Vessels	The veins and arteries of the HEART.	Coronary Arteries,Sinus Node Artery,Coronary Veins,Arteries, Coronary,Arteries, Sinus Node,Artery, Coronary,Artery, Sinus Node,Coronary Artery,Coronary Vein,Coronary Vessel,Sinus Node Arteries,Vein, Coronary,Veins, Coronary,Vessel, Coronary,Vessels, Coronary