alexa Extracellular superoxide dismutase in vessels and airways of humans and baboons.
Toxicology

Toxicology

Journal of Drug Metabolism & Toxicology

Author(s): Oury TD, Day BJ, Crapo JD

Abstract Share this page

Abstract Extracellular superoxide dismutase (EC SOD) is generally the least abundant SOD isozyme in tissues, while the intracellular Cu,Zn SOD is usually the most abundant isozyme. The biological significance of EC SOD is unknown. Immunolocalization studies show that EC SOD is in the connective tissue surrounding smooth muscle in vessels and airways within the lung. Endothelium derived relaxing factor, thought to be a nitric oxide (NO) species, is a primary mediator of vascular relaxation. During NO.'s diffusion between the endothelium and smooth muscle, extracellular superoxide would be the most efficient scavenger of NO(.). High levels of extracellular superoxide dismutase in vessels could, therefore, be essential to enable NO. to modulate vascular tone. To evaluate the hypothesis that vessel walls are functionally rich in extracellular superoxide scavenging capacity, this study quantitates the EC SOD levels in pulmonary and systemic vessels and in airways. Both pulmonary and systemic arteries in humans and baboons were found to contain high activities of EC SOD. The level of EC SOD in all human and baboon arteries examined is greater than or equal to the level of intracellular Cu,Zn SOD, and EC SOD accounted for over 70\% of the total SOD activity in some vessels examined. Immunolocalization of EC SOD in human and baboon vessels show similar distributions of this enzyme in pulmonary and systemic vessels. EC SOD is located beneath the endothelium, surrounding smooth muscle cells, and throughout the adventitia of vessels. The high level of EC SOD in vessels, and its localization between endothelial and smooth muscle cells, suggest that regulation of superoxide may be particularly important in this region, possibly in regulating vascular tone.
This article was published in Free Radic Biol Med and referenced in Journal of Drug Metabolism & Toxicology

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
 
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
 
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

 
© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version
adwords