Exercise training increases coronary transport reserve in miniature swine
| Autor: | M. J. Bhatte, K. A. Overholser, M. H. Laughlin |
|---|---|
| Rok vydání: | 1989 |
| Předmět: |
Physiology
Swine Hemodynamics Miniature swine Physical exercise Capillary Permeability Coronary circulation Dogs Species Specificity Physiology (medical) Coronary Circulation Physical Conditioning Animal medicine Animals Treadmill Edetic Acid business.industry Receptors Adrenergic alpha medicine.anatomical_structure YUCATAN MINIATURE SWINE Anesthesia Coronary vessel Circulatory system Swine Miniature Female business Blood Flow Velocity |
| Zdroj: | Journal of applied physiology (Bethesda, Md. : 1985). 67(3) |
| ISSN: | 8750-7587 |
| Popis: | Female yucatan miniature swine were trained on a treadmill (ET) or were cage confined (C) for 16–22 wk. The ET pigs had increased exercise tolerance, heart weight-to-body weight ratio, and skeletal muscle oxidative capacity. After anesthesia the left anterior descending coronary artery was cannulated and pump perfused with blood while aortic, central venous, and coronary perfusion pressures, electrocardiogram, heart rate, and coronary blood flow were monitored. Capillary permeability-surface area product (PS) for EDTA was determined with the single-injection indicator-diffusion method by use of an organ model based on the Sangren-Sheppard equations for capillary transport. Coronary blood flow (CBF) and PS were compared before and during maximal adenosine vasodilation with coronary perfusion pressures at 120 mmHg. Results indicate that there were no differences in base-line CBF or PS between C and ET groups. alpha-Receptor blockade with phentolamine and/or prazosin, before adenosine vasodilation, produced increases in PS in C pigs but had little effect in ET pigs. During maximal vasodilation with adenosine, ET pigs had greater CBF (447 +/- 24 vs. 366 +/- 27 ml.min-1.100 g-1) and greater PS (83 +/- 9 vs. 55 +/- 7 ml.min-1.100 g-1) than the C group. It is concluded that ET induces an increased coronary transport capacity in miniature swine that includes a 22% increase in blood flow capacity and a 51% increase in capillary exchange capacity. |
| Databáze: | OpenAIRE |
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