Aging induces muscle-specific impairment of endothelium-dependent dilation in skeletal muscle feed arteries

• Published in: Journal of applied physiology (1985) Vol. 93; no. 5; pp. 1685 - 1690
• Main Authors: Woodman, Christopher R, Price, Elmer M, Laughlin, M. Harold
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Physiological Soc 01.11.2002; American Physiological Society
• Subjects: Aging; Aging - physiology; Animals; Arteries - physiology; Biological and medical sciences; Blood vessels; Blood vessels and receptors; Endothelium, Vascular - physiology; Fundamental and applied biological sciences. Psychology; Male; Muscle, Skeletal - blood supply; Nitric oxide; Nitric Oxide Synthase - metabolism; Nitric Oxide Synthase Type III; Rats; Rats, Inbred F344; Sodium; Superoxide Dismutase - metabolism; Superoxide Dismutase-1; Vasodilation - physiology; Vertebrates: cardiovascular system; Senescence; Rat; Rodentia; Striated muscle; Soleus muscle; Artery; Vasodilation; Endothelium; Vasomotricity; Vertebrata; Mammalia; sodium nitroprusside; Blood vessel; Nitric oxide; superoxide dismutase; endothelial nitric oxide synthase; Circulatory system; Gastrocnemius muscle; acetylcholine
• DOI: 10.1152/japplphysiol.00461.2002
• ISSN: 8750-7587

Departments of Veterinary Biomedical Sciences and Physiology and Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri 65211 We tested the hypothesis that aging decreases endothelium-dependent vasodilation in feed arteries perfusing rat skeletal muscle. In addition, we tested the hypothesis that attenuated vasodilator responses are associated with decreased endothelial nitric oxide synthase (eNOS) and superoxide dismutase-1 (SOD-1) expression. Soleus feed arteries (SFA) and gastrocnemius feed arteries (GFA) were isolated from young (4 mo) and old (24 mo) male Fischer 344   rats. Feed arteries from the right hindlimb were cannulated with two glass micropipettes for examination of endothelium-dependent [acetylcholine (ACh)] and endothelium-independent [adenosine (Ado) or sodium nitroprusside (SNP)] vasodilator function. Feed arteries from the left hindlimb were frozen and used to assess eNOS and SOD-1 protein and mRNA expression. In SFA, endothelium-dependent dilation to ACh was reduced in old rats (0.9 ± 0.04 vs. 0.8 ±   0.03), whereas dilator responses to Ado and SNP were similar in SFA of young and old rats. In GFA, vasodilator responses to ACh, Ado, and SNP were not altered by age. eNOS and SOD-1 protein expression declined with age in SFA ( 71 and 54%, respectively) but not in GFA. eNOS and SOD-1 mRNA expression were not altered by age in SFA or GFA. Collectively, these data indicate aging induces muscle-specific impairment of endothelium-dependent vascular function in SFA. endothelial nitric oxide synthase; superoxide dismutase; nitric oxide; acetylcholine; sodium nitroprusside