Document Detail

Atrial and ventricular myocardial blood flows in horses at rest and during exercise.
MedLine Citation:
PMID:  7998705     Owner:  NLM     Status:  MEDLINE    
Right atrial, pulmonary artery, pulmonary capillary, pulmonary artery wedge, and systemic blood pressures of strenuously exercising horses increase markedly. As a consequence, myocardial metabolic O2 demand in exercising horses must be high. Experiments were, therefore, carried out on 9 healthy, exercise-conditioned horses (2.5 to 8 years old; 481 +/- 16 kg) to ascertain the regional distribution of myocardial blood supply in the atria and ventricles at rest and during exercise. Blood flow was measured, using 15-micron-diameter radionuclide-labeled microspheres that were injected into the left ventricle while reference blood samples were being withdrawn at a constant rate from the thoracic aorta. Myocardial blood flow was determined at rest and during 2 exercise bouts performed on a high-speed treadmill at 8 and 13 m/s (0% grade). The sequence of exercise bouts was randomized among horses, and a 60-minute rest period was permitted between exercise bouts. There was considerable heterogeneity in the distribution of myocardial perfusion in the atria and the ventricles at rest; the right atrial myocardium received significantly (P < 0.05) less perfusion than did the left atrium, and these values were significantly (P < 0.05) less than those for the respective ventricular myocardium. The right ventricular myocardial blood flow also was significantly less than that in the left ventricle. With exercise, myocardial blood flow in all regions increased progressively with increasing work intensity and marked coronary vasodilation was observed in all cardiac regions. During exercise at 8 or 13 m/s, right and left atrial myocardial blood flows (per unit weight basis) were not different from each other.(ABSTRACT TRUNCATED AT 250 WORDS)
M Manohar; T E Goetz; E Hutchens; E Coney
Related Documents :
10659285 - Frusemide and weight carriage alter the acid:base responses of horses to incremental an...
1932775 - Solcoseryl in prevention of stress-induced gastric lesions and healing of chronic ulcers.
8966985 - Effects of transporting horses facing either forwards or backwards on their behaviour a...
9028485 - Use of dew-point hygrometry, direct sweat collection, and measurement of body water los...
7591395 - Hypogonadism as a cause of recurrent muscle injury in a high level soccer player. a cas...
8440545 - The effect of moderate resistance weight training on peak arm aerobic power.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  American journal of veterinary research     Volume:  55     ISSN:  0002-9645     ISO Abbreviation:  Am. J. Vet. Res.     Publication Date:  1994 Oct 
Date Detail:
Created Date:  1995-01-19     Completed Date:  1995-01-19     Revised Date:  2008-11-21    
Medline Journal Info:
Nlm Unique ID:  0375011     Medline TA:  Am J Vet Res     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1464-9     Citation Subset:  IM    
Department of Veterinary Biosciences, College of Veterinary Medicine, University of Illinois at Urbana-Champaign 61801.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Coronary Circulation / physiology*
Heart Atria
Heart Ventricles
Horses / physiology*
Physical Exertion / physiology*

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Neutrophil accumulation in the large colon of horses during low-flow ischemia and reperfusion.
Next Document:  Evaluation of a single-injection method for estimating glomerular filtration rate in dogs with reduc...