1h-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one and phenylephrine

Topics: Animals; Aorta; COS Cells; Cyclic GMP; Guanosine Triphosphate; Male; Muscle Relaxation; Muscle, Smooth, Vascular; Nitric Oxide; Nitroglycerin; Nitroso Compounds; Oxadiazoles; Oxidation-Reduction; Phenylephrine; Quinoxalines; Rats; Rats, Sprague-Dawley; Xanthine; Xanthine Oxidase; Xanthines

Topics: 1-Methyl-3-isobutylxanthine; Animals; Arteries; Cyclic AMP; Cyclic GMP; Enzyme Inhibitors; Imines; In Vitro Techniques; Muscle, Smooth, Vascular; Niacinamide; Oxadiazoles; Phenylephrine; Phosphoric Diester Hydrolases; Quinoxalines; Rats; Rats, Wistar; Second Messenger Systems; Vasodilation; Vasodilator Agents

Topics: 1-Methyl-3-isobutylxanthine; Adrenergic alpha-Agonists; Animals; Animals, Newborn; Enzyme Inhibitors; Epithelium; Female; Male; Oxadiazoles; Phenylephrine; Phosphodiesterase Inhibitors; Quinoxalines; Rabbits; Receptors, Adrenergic, beta-2; Serotonin; Trachea

Topics: Animals; Aorta, Thoracic; Arsenites; Carbon Monoxide; Endothelium, Vascular; Enzyme Inhibitors; Guanylate Cyclase; Heme Oxygenase (Decyclizing); Hypoxia; In Vitro Techniques; Kinetics; Male; Muscle Contraction; Muscle, Smooth, Vascular; Nitric Oxide Donors; Nitroarginine; Oxadiazoles; Penicillamine; Phenylephrine; Protoporphyrins; Quinoxalines; Rats; Rats, Sprague-Dawley; Reference Values; S-Nitroso-N-Acetylpenicillamine; Sodium Compounds

Topics: Acetylcholine; Animals; Carbachol; Charybdotoxin; Cytochrome P-450 Enzyme Inhibitors; Dose-Response Relationship, Drug; Female; In Vitro Techniques; Indomethacin; Male; Miconazole; NG-Nitroarginine Methyl Ester; Nitric Oxide; Ouabain; Oxadiazoles; Peptides; Phenylephrine; Potassium; Potassium Channel Blockers; Quinoxalines; Rats; Rats, Sprague-Dawley; Renal Artery; Tetraethylammonium; Vasoconstriction; Vasoconstrictor Agents; Vasodilation

Topics: Animals; Dose-Response Relationship, Drug; Drug Tolerance; Enzyme Inhibitors; Femoral Artery; Glucosamine; Glutathione; Hemoglobins; In Vitro Techniques; NG-Nitroarginine Methyl Ester; Nitric Oxide Donors; Nitroglycerin; Nitroso Compounds; Oxadiazoles; Penicillamine; Perfusion; Phenylephrine; Quinoxalines; Rats; Rats, Wistar; S-Nitrosoglutathione; Vasoconstriction; Vasoconstrictor Agents; Vasodilator Agents

Topics: Animals; Dose-Response Relationship, Drug; Drug Tolerance; Enzyme Inhibitors; Femoral Artery; Glucosamine; Glutathione; Guanylate Cyclase; In Vitro Techniques; Male; Methemoglobin; Nitric Oxide Donors; Nitroglycerin; Nitroso Compounds; Oxadiazoles; Penicillamine; Phenylephrine; Quinoxalines; Rats; Rats, Wistar; S-Nitroso-N-Acetylpenicillamine; S-Nitrosoglutathione; Vasoconstrictor Agents; Vasodilation

Topics: 3',5'-Cyclic-GMP Phosphodiesterases; Animals; Aorta, Thoracic; Arginine; Cyclic Nucleotide Phosphodiesterases, Type 5; Dose-Response Relationship, Drug; Electric Stimulation; In Vitro Techniques; Isoproterenol; Isoquinolines; Male; Muscle Relaxation; NG-Nitroarginine Methyl Ester; Nitroprusside; Oxadiazoles; Papaverine; Penis; Phenylephrine; Phosphodiesterase Inhibitors; Phosphoric Diester Hydrolases; Piperazines; Purines; Pyridines; Quinoxalines; Rabbits; Rats; Rats, Wistar; Sildenafil Citrate; Sulfones; Tetrodotoxin; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents

Topics: Animals; Arteries; Enzyme Activation; Enzyme Inhibitors; Female; Flavonoids; Histological Techniques; In Vitro Techniques; Mitogen-Activated Protein Kinases; Muscle, Smooth, Vascular; Osmolar Concentration; Oxadiazoles; Phenylephrine; Phosphorylation; Quinoxalines; Rabbits; Time Factors; Vasoconstriction; Vasoconstrictor Agents; Vasodilation

Topics: Acetylcysteine; Animals; Aorta, Thoracic; Endothelium, Vascular; Enzyme Inhibitors; Glutathione; Hydrogen-Ion Concentration; In Vitro Techniques; Male; Muscle Relaxation; Muscle, Smooth, Vascular; Nitric Oxide; Nitroso Compounds; Oxadiazoles; Phenylephrine; Potassium Channel Blockers; Potassium Chloride; Quinoxalines; Rats; Rats, Wistar; Ryanodine; S-Nitrosoglutathione; Thapsigargin; Vasoconstrictor Agents; Vasodilation

Topics: Adenosine Triphosphate; Adrenergic alpha-Agonists; Animals; Enzyme Activation; Enzyme Inhibitors; Glyburide; Guanylate Cyclase; Male; Muscle Contraction; Muscle Relaxation; Muscle, Smooth; Nicorandil; Nitroprusside; Oxadiazoles; Penis; Phenylephrine; Potassium Channels; Quinoxalines; Rabbits; Vasodilator Agents

Topics: Acetylcholine; Animals; Aorta, Thoracic; Blood Pressure; Dose-Response Relationship, Drug; Endothelium, Vascular; Female; In Vitro Techniques; NG-Nitroarginine Methyl Ester; Nitrates; Nitrites; Nitroprusside; Oxadiazoles; Phenylephrine; Pregnancy; Quinoxalines; Rats; Rats, Sprague-Dawley; Sodium Chloride, Dietary; Uterus; Vasoconstrictor Agents; Vasodilator Agents

Topics: 3',5'-Cyclic-GMP Phosphodiesterases; Acetylcholine; Adrenergic alpha-Agonists; Adrenergic alpha-Antagonists; Animals; Clonidine; Cyclic GMP; Cyclic Nucleotide Phosphodiesterases, Type 5; Dose-Response Relationship, Drug; Endothelium, Vascular; Enzyme Inhibitors; Guanylate Cyclase; In Vitro Techniques; Mesenteric Arteries; Nitric Oxide; Nitroarginine; Oxadiazoles; Oxidopamine; Phenylephrine; Phosphodiesterase Inhibitors; Phosphoric Diester Hydrolases; Piperazines; Purines; Quinoxalines; Rats; Rats, Sprague-Dawley; Receptors, Adrenergic, alpha-2; Saponins; Sildenafil Citrate; Solubility; Sulfones; Sympatholytics; Time Factors; Vascular Resistance; Vasodilation; Vasodilator Agents; Yohimbine

Topics: Acetylcholine; Animals; Antineoplastic Agents; Cyclic GMP; Endothelium, Vascular; Enzyme Inhibitors; Female; Hypertension; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitroprusside; Oxadiazoles; Phenylephrine; Pregnancy; Pregnancy Complications, Cardiovascular; Quinoxalines; Rats; Rats, Sprague-Dawley; Tumor Necrosis Factor-alpha; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents

Topics: Animals; Cells, Cultured; Cyclic GMP; Dose-Response Relationship, Drug; Drug Synergism; Enzyme Inhibitors; Guanylate Cyclase; In Vitro Techniques; Indazoles; Male; Muscle Contraction; Muscle, Smooth; Nitric Oxide; Nitroprusside; Oxadiazoles; Penile Erection; Penis; Phenylephrine; Quinoxalines; Rabbits; Rats; Rats, Wistar; Signal Transduction; Vasoconstrictor Agents; Vasodilator Agents

Topics: Animals; Aorta, Thoracic; Endotoxemia; Enzyme Inhibitors; Escherichia coli; In Vitro Techniques; Lipopolysaccharides; Male; Muscle Contraction; Muscle Relaxation; Muscle, Smooth, Vascular; Nitric Oxide; Ouabain; Oxadiazoles; Phenylephrine; Potassium Channels, Inwardly Rectifying; Quinoxalines; Rats; Rats, Inbred WKY; Sodium-Potassium-Exchanging ATPase; Time Factors

Topics: 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; Acetylcholine; Animals; Aorta, Thoracic; Atrial Natriuretic Factor; Cyclic GMP; Dose-Response Relationship, Drug; Drug Antagonism; Drug Synergism; Guanylate Cyclase; Male; Mesenteric Arteries; Mice; Mice, Inbred Strains; Mice, Knockout; Muscle Relaxation; Natriuretic Peptide, C-Type; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Nitrogen Oxides; Nitroglycerin; Oxadiazoles; Phenylephrine; Polysaccharides; Quinoxalines; Receptors, Atrial Natriuretic Factor; Signal Transduction; Spermine

Topics: Amidines; Animals; Aorta, Thoracic; Benzylamines; Diet; Dose-Response Relationship, Drug; Enzyme Inhibitors; Escherichia coli; In Vitro Techniques; Injections, Intraperitoneal; Interleukin-1; Lipopolysaccharides; Magnesium Deficiency; Male; Muscle Contraction; Muscle, Smooth, Vascular; Oxadiazoles; Phenylephrine; Quinoxalines; Rats; Rats, Wistar; Receptors, Tumor Necrosis Factor; RNA, Messenger; Tumor Necrosis Factor-alpha

Topics: Animals; Aorta, Thoracic; Asteraceae; Brazil; Diterpenes; Dose-Response Relationship, Drug; Endothelium, Vascular; Ethanol; Indomethacin; Male; Muscle, Smooth, Vascular; NG-Nitroarginine Methyl Ester; Nifedipine; Oxadiazoles; Phenylephrine; Plant Extracts; Plant Roots; Quinoxalines; Rats; Rats, Wistar; Tetraethylammonium; Vasoconstriction; Vasodilation

Topics: Adolescent; Adult; Child; Cyclic GMP; Drug Evaluation, Preclinical; Electric Stimulation; Enzyme Inhibitors; Humans; In Vitro Techniques; Male; Muscle Contraction; Muscle Relaxation; Muscle, Smooth; Neurotoxins; NG-Nitroarginine Methyl Ester; Nitric Oxide; Oxadiazoles; Penis; Phenylephrine; Piperazines; Priapism; Purines; Quinoxalines; Scorpion Venoms; Second Messenger Systems; Sildenafil Citrate; Sodium Channel Blockers; Sulfones; Tetrodotoxin

Topics: Acetylcholine; Animals; Blotting, Western; Cyclic GMP; Endothelium, Vascular; Enzyme Inhibitors; Estradiol; Female; Interleukin-6; Isometric Contraction; Muscle Contraction; Muscle Relaxation; Muscle, Smooth, Vascular; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Nitrites; Oxadiazoles; Phenylephrine; Pregnancy; Pregnancy, Animal; Progesterone; Quinoxalines; Rats; Rats, Sprague-Dawley; Vasodilator Agents

Topics: Adult; Animals; Ascorbic Acid; Copper; Female; Humans; Mesenteric Arteries; Mice; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Donors; Nitroso Compounds; Oxadiazoles; Oxidative Stress; Phenylephrine; Pre-Eclampsia; Pregnancy; Quinoxalines; Serum Albumin, Bovine; Vasodilation

Topics: Acetylcholine; Adenosine Triphosphate; Animals; Calcium; Cyclooxygenase Inhibitors; Dose-Response Relationship, Drug; Endothelium, Vascular; Enzyme Inhibitors; Guanylate Cyclase; Horses; In Vitro Techniques; Indomethacin; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide Donors; Nitric Oxide Synthase; Nitroarginine; Oxadiazoles; Penis; Phenylephrine; Potassium; Potassium Channel Blockers; Potassium Channels; Quinoxalines; Sodium Nitrite; Tetraethylammonium; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents; Veins

Topics: Animals; Aorta; Calcium Chloride; Dose-Response Relationship, Drug; Drug Synergism; Endothelium, Vascular; In Vitro Techniques; Male; Marine Toxins; Methylene Blue; Oxadiazoles; Oxazoles; Peroxynitrous Acid; Phenylephrine; Piperazines; Potassium; Purines; Quinoxalines; Rats; Rats, Wistar; Sildenafil Citrate; Sulfones; Tetraethylammonium; Vasoconstriction; Vasoconstrictor Agents; Vasodilation

Topics: Amides; Animals; Blotting, Western; Celiac Artery; Cyclic GMP; Cyclooxygenase Inhibitors; Dose-Response Relationship, Drug; Enzyme Inhibitors; Gene Expression; Guanine Nucleotide Exchange Factors; Guanylate Cyclase; In Vitro Techniques; Indomethacin; Intracellular Signaling Peptides and Proteins; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase; Nitroprusside; Oxadiazoles; Phenylephrine; Potassium; Protein Serine-Threonine Kinases; Pyridines; Quinoxalines; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction; Rho Guanine Nucleotide Exchange Factors; rho-Associated Kinases; rhoA GTP-Binding Protein; RNA, Messenger; Signal Transduction; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents

Topics: 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; Acetylcholine; Animals; Blotting, Western; Cyclic GMP; Enzyme Inhibitors; Guanylate Cyclase; Hydroquinones; Iliac Artery; In Vitro Techniques; Nitric Oxide; Nitric Oxide Donors; Oxadiazoles; Penicillamine; Phenylephrine; Phosphoproteins; Phosphorylation; Protein Tyrosine Phosphatases; Quinoxalines; Serine; Signal Transduction; Swine; Triazoles; Tyrosine; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents

Topics: Acetylcholine; Aging; Animals; Aorta; Arginase; Arginine; Calcium; Drug Synergism; Enzyme Inhibitors; In Vitro Techniques; Male; Nitric Oxide; Nitric Oxide Synthase; Oligonucleotides, Antisense; Oxadiazoles; Phenylephrine; Quinoxalines; Rats; Rats, Wistar; Signal Transduction; Up-Regulation; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents

Topics: Angiotensin II; Angiotensin II Type 1 Receptor Blockers; Animals; Carotid Arteries; Dose-Response Relationship, Drug; Drug Antagonism; In Vitro Techniques; Male; NG-Nitroarginine Methyl Ester; Oxadiazoles; Peptide Fragments; Phenylephrine; Quinoxalines; Rats; Rats, Wistar; Saralasin; Vasoconstrictor Agents; Vasodilation

Topics: Animals; Ascorbic Acid; Boron Compounds; Connexin 43; Connexins; Dose-Response Relationship, Drug; Endothelium, Vascular; Gap Junction alpha-4 Protein; Gap Junction alpha-5 Protein; Gap Junctions; Hydrazines; Iliac Artery; Indoles; Indomethacin; Male; Membrane Potentials; Nitric Oxide Donors; Nitric Oxide Synthase Type III; Nitroprusside; Oxadiazoles; Phenylephrine; Quinoxalines; Rabbits; Vasodilation

Topics: Aged; Analysis of Variance; Coronary Artery Bypass; Cyclic GMP; Dose-Response Relationship, Drug; Enzyme Activators; Enzyme Inhibitors; Female; Humans; Hydrazines; In Vitro Techniques; Indazoles; Male; Middle Aged; Nitric Oxide Donors; Oxadiazoles; Peptides; Phenylephrine; Potassium Channels, Calcium-Activated; Quinoxalines; Radial Artery; Vasoconstrictor Agents; Vasodilation

Topics: Adamantane; Animals; Arteries; Endothelium, Vascular; Glyburide; In Vitro Techniques; KATP Channels; Male; Mesenteric Arteries; Mice; Mice, Inbred C57BL; Morpholines; Muscle Relaxation; Muscle, Smooth, Vascular; Oxadiazoles; Phenylephrine; Potassium Channel Blockers; Quinoxalines; Sulfonylurea Compounds; Vascular Resistance; Vasoconstrictor Agents

Topics: Acetylcholine; Animals; Aorta, Thoracic; Arginine; Autonomic Denervation; Blood Pressure; Dose-Response Relationship, Drug; Endothelium, Vascular; Enzyme Inhibitors; Guanylate Cyclase; Heart Rate; Indomethacin; Male; Muscle Contraction; Muscle, Smooth, Vascular; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitroprusside; Oxadiazoles; Oxyhemoglobins; Phenylephrine; Quinoxalines; Rats

Topics: Aminoquinolines; Animals; Carotid Artery, Internal; Catalase; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Cyclooxygenase Inhibitors; Dogs; Dose-Response Relationship, Drug; Enzyme Inhibitors; Ethanol; Free Radical Scavengers; Guanylate Cyclase; Humans; Hydrogen Peroxide; Hydroquinones; In Vitro Techniques; Indomethacin; Mannitol; Mesenteric Artery, Superior; Methylene Blue; Muramidase; Nitric Oxide; Nitric Oxide Synthase; omega-N-Methylarginine; Oxadiazoles; Phenylephrine; Prostaglandins; Protein Kinase Inhibitors; Quinoxalines; Receptors, Cytoplasmic and Nuclear; Sepsis; Signal Transduction; Soluble Guanylyl Cyclase; Thionucleotides; Time Factors; Vasoconstrictor Agents; Vasodilation

Topics: Analysis of Variance; Animals; Arginine; Electric Stimulation; Lithium Chloride; Male; Muscle Relaxation; Muscle, Smooth; NG-Nitroarginine Methyl Ester; Nitrergic Neurons; Nitric Oxide; Nitric Oxide Synthase Type I; Nitroprusside; Oxadiazoles; Phenylephrine; Quinoxalines; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction

Topics: Acetylcysteine; Animals; Calcium; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Guanylate Cyclase; Muscle Contraction; Muscle, Smooth, Vascular; Nitric Oxide; Nitric Oxide Synthase Type III; omega-N-Methylarginine; Oxadiazoles; Phenylephrine; Potassium Channel Blockers; Potassium Channels, Voltage-Gated; Protein Kinase C; Quinoxalines; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Vasoconstrictor Agents; Vasodilation

Topics: Animals; Biological Factors; Data Interpretation, Statistical; Dose-Response Relationship, Drug; Endothelium, Vascular; Enzyme Inhibitors; Male; Mesenteric Artery, Superior; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase Type I; Oxadiazoles; Phenylephrine; Quinoxalines; Rats; Rats, Wistar; Thiazoles; Vasoconstrictor Agents; Vasodilation; Vasodilator Agents

Topics: 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; Animals; Benzophenanthridines; Body Weight; Calcium; Chick Embryo; Egtazic Acid; Endothelin-1; Enzyme Inhibitors; Femoral Artery; Hypoxia; NG-Nitroarginine Methyl Ester; Oxadiazoles; Phenylephrine; Phorbol 12,13-Dibutyrate; Potassium Chloride; Protein Kinase C; Protein Kinase Inhibitors; Quinoxalines; rho-Associated Kinases; Vasoconstriction

Topics: Animals; Dose-Response Relationship, Drug; Drug Tolerance; Electrophoresis, Capillary; Endothelium, Vascular; In Vitro Techniques; Isosorbide Dinitrate; Magnetic Resonance Spectroscopy; Male; Mesenteric Arteries; Muscle Relaxation; Muscle, Smooth, Vascular; Oxadiazoles; Phenylephrine; Quinoxalines; Rats; Rats, Wistar; Spectrophotometry, Infrared; Stereoisomerism; Vasoconstrictor Agents; Vasodilator Agents

Topics: Androstadienes; Angiotensin II; Animals; Aorta, Thoracic; Chromones; Endothelium, Vascular; Guanylate Cyclase; Isometric Contraction; Male; Morpholines; Muscle, Smooth, Vascular; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase Type III; Oxadiazoles; Phenylephrine; Phosphatidylinositol 3-Kinase; Phosphoinositide-3 Kinase Inhibitors; Potassium; Proto-Oncogene Proteins c-akt; Quinoxalines; Rats; Rats, Wistar; Receptors, G-Protein-Coupled; Signal Transduction; Wortmannin

Topics: Animals; Aorta, Thoracic; Guanylate Cyclase; In Vitro Techniques; Male; Muscle, Smooth, Vascular; Nitric Oxide; Nitric Oxide Donors; Oxadiazoles; Phenylephrine; Phosphoric Diester Hydrolases; Prodrugs; Quinoxalines; Rats; Rats, Wistar; Receptors, Cytoplasmic and Nuclear; Ruthenium Compounds; Soluble Guanylyl Cyclase; Vasodilation; Vasodilator Agents

Topics: Animals; Artemisia; Chromones; Cyclic AMP; Cyclic GMP; Cyclic Nucleotide Phosphodiesterases, Type 5; Drug Evaluation, Preclinical; Ethanol; Male; Muscle Relaxation; NG-Nitroarginine Methyl Ester; Nitric Oxide; Oxadiazoles; Penile Erection; Penis; Phenylephrine; Phosphodiesterase 5 Inhibitors; Plant Extracts; Quinoxalines; Rabbits; Radioimmunoassay; Signal Transduction

Topics: Animals; Free Radical Scavengers; Glycerol; Guanylate Cyclase; In Vitro Techniques; Intracellular Space; Male; Mesenteric Arteries; Myocytes, Smooth Muscle; Nitrates; Nitric Oxide; Nitric Oxide Donors; Oxadiazoles; Phenylephrine; Potassium Channel Blockers; Potassium Channels; Propane; Quinoxalines; Rats; Rats, Wistar; Receptors, Cytoplasmic and Nuclear; Soluble Guanylyl Cyclase; Vasoconstriction; Vasodilation; Vasodilator Agents

Topics: Animals; Aorta; Atrial Natriuretic Factor; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Dipeptides; Human Umbilical Vein Endothelial Cells; Humans; In Vitro Techniques; Male; Methylene Blue; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Oxadiazoles; Phenylephrine; Phosphorylation; Potassium Channel Blockers; Potassium Channels; Propanols; Quinoxalines; Rats; Rats, Sprague-Dawley; rho-Associated Kinases; Signal Transduction; Vasoconstriction; Vasodilation

Topics: Animals; Aorta; Calcium; Citrus; Dinoprost; Endothelium, Vascular; Enzyme Inhibitors; Extracellular Space; Guanylate Cyclase; Inositol 1,4,5-Trisphosphate Receptors; Intracellular Space; Isometric Contraction; Male; Mice, Inbred C57BL; Muscle, Smooth, Vascular; Oils, Volatile; Oxadiazoles; Phenylephrine; Quinoxalines; Ryanodine Receptor Calcium Release Channel; Vasodilation; Vasodilator Agents