Back to Search
Start Over
Superoxide radical formation and associated biochemical alterations in the plasma membrane of brain, heart, and liver during the lifetime of the rat.
- Source :
-
Journal of cellular biochemistry [J Cell Biochem] 1992 Mar; Vol. 48 (3), pp. 296-304. - Publication Year :
- 1992
-
Abstract
- Plasma membrane samples from rat brain, heart, and liver were examined for biochemical changes with age. A rise in superoxide radical (SOR) levels was followed by increases in thiobarbituric acid reactive substances and decreases in membrane fluidity with age. The earliest rise in SOR formation appeared in the plasma membrane from the brain. With age, protein synthesis also decreased significantly in tissue homogenates from brain and heart but was unchanged in the liver. Exposure of plasma membrane samples to in vitro-elevated SOR levels stimulated formation of lipid peroxides, as indicated by the thiobarbituric acid test, and resulted in a decrease in membrane fluidity in each tissue and in a decline in protein synthesis in brain and heart. Changes in brain lipid peroxidation and in membrane fluidity in brain and heart as a result of SOR supplementation were further enhanced due to age. In addition, the mechanism of SOR formation was examined in plasma membrane samples from the brain. SOR generation was Ca(2+)-sensitive, blocked by superoxide dismutase or vitamin E and inhibited by both indomethacin, a cyclooxygenase inhibitor, and bromophenacyl bromide, a phospholipase A2 inhibitor. These results show significant increases in SOR formation and biochemical alterations in plasma membranes from brain, heart, and liver in aging rats. SOR formation appears to be enzyme-mediated and elevated levels of this oxygen radical could be involved in membrane breakdown in older rats.
- Subjects :
- Animals
Brain growth & development
Brain ultrastructure
Calcium metabolism
Cell Membrane drug effects
Heart growth & development
Lipid Peroxidation
Liver growth & development
Liver ultrastructure
Male
Membrane Fluidity
Myocardium ultrastructure
Rats
Rats, Wistar
Thiobarbiturates pharmacology
Aging metabolism
Brain metabolism
Cell Membrane metabolism
Liver metabolism
Myocardium metabolism
Superoxides metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0730-2312
- Volume :
- 48
- Issue :
- 3
- Database :
- MEDLINE
- Journal :
- Journal of cellular biochemistry
- Publication Type :
- Academic Journal
- Accession number :
- 1328256
- Full Text :
- https://doi.org/10.1002/jcb.240480310