Biomaterial Database

Transient oxygen uptake during myocardial reactive hyperemia in the dog. 1978

J H Ruiter, and J A Spaan, and J D Laird

Oxygen uptake during myocardial hyperemia (MRH) following occlusions of 2.5-30 s was studied in nine anesthetized open-chest dogs by continuous measurement of left anterior coronary blood flow and anterior coronary vein oxygen saturation with electromagnetic flowmeter and fiber-optic catheters, respectively. The ratio of excess oxygen uptake to debt multiplied by 100% was defined as the oxygen repayment ratio (RR) and varied between -50% and +150% (mean 78%). Application of a steady-state Fick formula, as used by previous investigators, results in a profound overestimate of the RR (70-400%, mean 295%). RR is severely distorted by the venous catheter system, and after consideration of these effects we would conclude that the "true" RR in MRH is even lower than we found. Comparing our results with steady-state exercise autoregulation leads us to the following conclusions: 1) chemical kinetic limitations in oxygen release by red blood cells are excluded, 2) a simple direct PO2 regulation of flow is unlikely, but 3) our results are not inconsistent with a more complex integral oxygen regulation or with the metabolic hypothesis.

UI	MeSH Term	Description	Entries
D008433	Mathematics	The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Mathematic
D009206	Myocardium	The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.	Muscle, Cardiac,Muscle, Heart,Cardiac Muscle,Myocardia,Cardiac Muscles,Heart Muscle,Heart Muscles,Muscles, Cardiac,Muscles, Heart
D010100	Oxygen	An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.	Dioxygen,Oxygen-16,Oxygen 16
D010101	Oxygen Consumption	The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)	Consumption, Oxygen,Consumptions, Oxygen,Oxygen Consumptions
D012039	Regional Blood Flow	The flow of BLOOD through or around an organ or region of the body.	Blood Flow, Regional,Blood Flows, Regional,Flow, Regional Blood,Flows, Regional Blood,Regional Blood Flows
D003326	Coronary Circulation	The circulation of blood through the CORONARY VESSELS of the HEART.	Circulation, Coronary
D004285	Dogs	The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)	Canis familiaris,Dog
D006706	Homeostasis	The processes whereby the internal environment of an organism tends to remain balanced and stable.	Autoregulation
D006940	Hyperemia	The presence of an increased amount of blood in a body part or an organ leading to congestion or engorgement of blood vessels. Hyperemia can be due to increase of blood flow into the area (active or arterial), or due to obstruction of outflow of blood from the area (passive or venous).	Active Hyperemia,Arterial Hyperemia,Passive Hyperemia,Reactive Hyperemia,Venous Congestion,Venous Engorgement,Congestion, Venous,Engorgement, Venous,Hyperemia, Active,Hyperemia, Arterial,Hyperemia, Passive,Hyperemia, Reactive,Hyperemias,Hyperemias, Reactive,Reactive Hyperemias
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia