|
|
||||||||
Departments of Veterinary Biomedical Sciences and Medical Physiology, University of Missouri, Columbia, Missouri 65211
The hyperemic response in exercising skeletal muscle is dependent on muscle fiber-type composition and fiber recruitment patterns, but the vascular control mechanisms producing exercise hyperemia in skeletal muscle remain poorly understood. The purpose of this study was to test the hypothesis that arterioles from white, low-oxidative skeletal muscle are less responsive to adenosine-induced dilation than are arterioles from diaphragm (Dia) and red, high-oxidative skeletal muscle. Second-order arterioles (2As) were isolated from the white portion of gastrocnemius muscle (WG; low-oxidative, fast-twitch muscle tissue) and two types of high-oxidative skeletal muscle [Dia and red portion of gastrocnemius muscle (RG)] of rats. Results reveal that 2As from all three types of muscle dilated in response to the endothelium-dependent dilator acetylcholine (WG: 48 ± 3%, Dia: 51 ± 3%, RG: 74 ± 3%). In contrast, adenosine dilated only 2As from WG (48 ± 4%) and Dia (46 ± 5%) but not those from RG (5 ± 5%). Thus adenosine-induced dilator responses differed among 2As of these different types of muscle tissue. However, the results do not support our hypothesis because 2As from Dia and WG dilated in response to adenosine, whereas 2As from RG did not. We conclude that the adenosine responsiveness of 2As from rat skeletal muscle cannot be predicted only by the fiber-type composition or oxidative capacity of the skeletal muscle tissue wherein the arteriole lies.
arteries; blood flow; endothelium; endothelial-derived factors; exercise
This article has been cited by other articles:
![]() |
L. M. Romer and M. I. Polkey Exercise-induced respiratory muscle fatigue: implications for performance J Appl Physiol, March 1, 2008; 104(3): 879 - 888. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Wang and V. H. Huxley Adenosine A2A receptor modulation of juvenile female rat skeletal muscle microvessel permeability Am J Physiol Heart Circ Physiol, December 1, 2006; 291(6): H3094 - H3105. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. McDonough, B. J. Behnke, T. I. Musch, and D. C. Poole Effects of chronic heart failure in rats on the recovery of microvascular PO2 after contractions in muscles of opposing fibre type Exp Physiol, July 1, 2004; 89(4): 473 - 485. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. H. Laughlin, C. R. Woodman, W. G. Schrage, D. Gute, and E. M. Price Interval sprint training enhances endothelial function and eNOS content in some arteries that perfuse white gastrocnemius muscle J Appl Physiol, January 1, 2004; 96(1): 233 - 244. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. H. Andrade, A. P. Merriam, W. Guo, G. Cheng, C. A. McMullen, K. Hayess, P. F. M. van der Ven, and J. D. Porter Paradoxical absence of M lines and downregulation of creatine kinase in mouse extraocular muscle J Appl Physiol, August 1, 2003; 95(2): 692 - 699. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. R. Woodman, E. M. Price, and M. H. Laughlin Aging induces muscle-specific impairment of endothelium-dependent dilation in skeletal muscle feed arteries J Appl Physiol, November 1, 2002; 93(5): 1685 - 1690. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |