Journal of Applied Physiology, Vol 45, Issue 4 604-610, Copyright © 1978 by American Physiological Society

ARTICLES

Effects of exercise training on coronary reactive hyperemia and blood flow in the dog

M. H. Laughlin, J. N. Diana and C. M. Tipton

The reactive hyperemic responses to 10-s coronary occlusions were studied in seven sedentary-control (C) and eight exercise-trained (T) anesthetized dogs, with electromagnetic flowmeters placed on the left anterior descending coronary artery. Radiolabeled microspheres (9 +/- 0.8 micron) were used to measure resting coronary flow per gram and to study the effects of isoproterenol infusion (ISO) (1 mg/kg-min) on total and regional coronary flow. Base-line coronary flow per 100 g was significantly greater in the T dogs (122 +/- 7) than in C dogs (100 +/- 4). During ISO, T and C coronary resistances did not differ significantly, whereas the effects of ISO on total and regional coronary flow were quite different in T dogs as compared to C dogs. C and T hyperemic flow debt repayments did not differ significantly; however, the peak reactive hyperemic flow in T dogs (344 +/- 12%) was significantly greater than the control (306 +/- 10%). Since resting coronary flow per gram was greater in T dogs, the greater peak reactive hyperemic flow implies that T dogs have an increased coronary reserve. Although the mechanisms involved are unclear, the results of this study indicate that chronic exercise training may have beneficial effects on coronary physiology.

This article has been cited by other articles:

				D. J. Duncker and R. J. Bache Regulation of Coronary Blood Flow During Exercise Physiol Rev, July 1, 2008; 88(3): 1009 - 1086. [Abstract] [Full Text] [PDF]

				D J R Hildick-Smith, P J Johnson, C R Wisbey, E M Winter, and L M Shapiro Coronary flow reserve is supranormal in endurance athletes: an adenosine transthoracic echocardiographic study Heart, October 1, 2000; 84(4): 383 - 389. [Abstract] [Full Text]

				M. Kozakova, F. Galetta, L. Gregorini, G. Bigalli, F. Franzoni, C. Giusti, and C. Palombo Coronary Vasodilator Capacity and Epicardial Vessel Remodeling in Physiological and Hypertensive Hypertrophy Hypertension, September 1, 2000; 36(3): 343 - 349. [Abstract] [Full Text] [PDF]

				T. O. Takala, P. Nuutila, C. Katoh, M. Luotolahti, J. Bergman, M. Maki, V. Oikonen, U. Ruotsalainen, T. Gronroos, M. Haaparanta, et al. Myocardial blood flow, oxygen consumption, and fatty acid uptake in endurance athletes during insulin stimulation Am J Physiol Endocrinol Metab, October 1, 1999; 277(4): E585 - E590. [Abstract] [Full Text] [PDF]

				M. H. Laughlin and J. M. Muller Vasoconstrictor responses of coronary resistance arteries in exercise-trained pigs J Appl Physiol, March 1, 1998; 84(3): 884 - 889. [Abstract] [Full Text] [PDF]

				J. Wang, G.-H. Yi, M. Knecht, B.-l. Cai, S. Poposkis, M. Packer, and D. Burkhoff Physical Training Alters the Pathogenesis of Pacing-Induced Heart Failure Through Endothelium-Mediated Mechanisms in Awake Dogs Circulation, October 21, 1997; 96(8): 2683 - 2692. [Abstract] [Full Text]

				G. Zhao, X. Zhang, X. Xu, M. Ochoa, and T. H. Hintze Short-term Exercise Training Enhances Reflex Cholinergic Nitric Oxide–Dependent Coronary Vasodilation in Conscious Dogs Circ. Res., June 19, 1997; 80(6): 868 - 876. [Abstract] [Full Text]