Hyperemic response of the coronary circulation to brief diastolic occlusion in the conscious dog. 1982

G G Schwartz, and P A McHale, and J C Greenfield

This study was undertaken to determine whether coronary blood flow can be regulated in response to coronary arterial occlusions briefer than a single diastole. The possible involvement of metabolic vs. myogenic mechanisms in such regulation was investigated. Eleven conscious dogs with experimentally produced complete heart block, chronically implanted electromagnetic flow probes, and pneumatic occluders on the left circumflex coronary artery were studied. Diastolic coronary occlusions lasting 100 to 400 msec were performed at paced heart rates of 40, 60, and 120 beats/min. At a heart rate of 60 beats/min, a 200-msec occlusion was sufficiently long to produce a significant reactive hyperemic response; 400-mec occlusions resulted in larger responses, while 100-msec occlusions did not generate a discernible response. The onset of reactive hyperemia was delayed from the end of the occlusion until the first post-occlusion systole. The length of this delay could be altered by changing the heart rate or occlusion duration, but no significant response was detected before the first post-occlusion systole. This characteristic of the data is more consistent with a metabolic than with a myogenic mechanism. If the response is metabolic, the data demonstrate that autoregulation of coronary flow by such a mechanism is very rapid, occurring during the first systole in which a flow deficit is detected by the myocardium.

UI MeSH Term Description Entries
D009200 Myocardial Contraction Contractile activity of the MYOCARDIUM. Heart Contractility,Inotropism, Cardiac,Cardiac Inotropism,Cardiac Inotropisms,Contractilities, Heart,Contractility, Heart,Contraction, Myocardial,Contractions, Myocardial,Heart Contractilities,Inotropisms, Cardiac,Myocardial Contractions
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
D003326 Coronary Circulation The circulation of blood through the CORONARY VESSELS of the HEART. Circulation, Coronary
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
D003971 Diastole Post-systolic relaxation of the HEART, especially the HEART VENTRICLES. Diastoles
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
D006339 Heart Rate The number of times the HEART VENTRICLES contract per unit of time, usually per minute. Cardiac Rate,Chronotropism, Cardiac,Heart Rate Control,Heartbeat,Pulse Rate,Cardiac Chronotropy,Cardiac Chronotropism,Cardiac Rates,Chronotropy, Cardiac,Control, Heart Rate,Heart Rates,Heartbeats,Pulse Rates,Rate Control, Heart,Rate, Cardiac,Rate, Heart,Rate, Pulse
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
D001157 Arterial Occlusive Diseases Pathological processes which result in the partial or complete obstruction of ARTERIES. They are characterized by greatly reduced or absence of blood flow through these vessels. They are also known as arterial insufficiency. Arterial Obstructive Diseases,Arterial Occlusion,Arterial Obstructive Disease,Arterial Occlusions,Arterial Occlusive Disease,Disease, Arterial Obstructive,Disease, Arterial Occlusive,Obstructive Disease, Arterial,Occlusion, Arterial,Occlusive Disease, Arterial

Related Publications

G G Schwartz, and P A McHale, and J C Greenfield
June 1989, The American journal of physiology,
G G Schwartz, and P A McHale, and J C Greenfield
May 1991, Circulation research,
G G Schwartz, and P A McHale, and J C Greenfield
January 1986, Heart and vessels,
G G Schwartz, and P A McHale, and J C Greenfield
July 1987, The American journal of physiology,
G G Schwartz, and P A McHale, and J C Greenfield
June 1972, The American journal of pathology,
G G Schwartz, and P A McHale, and J C Greenfield
May 1973, Circulation research,
G G Schwartz, and P A McHale, and J C Greenfield
December 1981, The American journal of cardiology,
G G Schwartz, and P A McHale, and J C Greenfield
August 1972, Circulation research,
G G Schwartz, and P A McHale, and J C Greenfield
July 1983, The American journal of cardiology,
G G Schwartz, and P A McHale, and J C Greenfield
November 1984, Federation proceedings,
Copied contents to your clipboard!