A comparative study of superoxide dismutase activity in polymorphonuclear leukocytes, monocytes, and alveolar macrophages of the guinea pig

✍ Scribed by Dr. Manfred Rister; Robert L. Baehner

• Publisher: John Wiley and Sons
• Year: 1976
• Tongue: English
• Weight: 993 KB
• Volume: 87
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1040870310

✦ Synopsis

Abstract

Superoxide dismutase, an enzyme which catalyzes the dismutation of superoxide radical formed during the univalent reduction of oxygen, was quantitated by observing the inhibition of cytochrome C reduction in three cell fractions in guinea pig peritoneal PMNs and monocytes and compared to alveolar macrophages. No differences were found in the 16,000 × g pellets containing mitochondria, membranes, and granules and representing 96% of total SOD activity in PMNs and monocytes but only 48% total SOD activity in alveolar macrophages. The 100,000 × g microsomal pellet of alveolar macrophages contained 8% of total SOD activity and two‐five times more activity than the respective fractions from monocytes and PMNs. However, there was 70 times more SOD in the 100,000 × g supernatant from alveolar macrophages containing 44% of total enzyme activity than in the same fraction of PMNs and monocytes containing less than 2% total SOD activity. SOD activity is mainly located in the 16,000 × g particulate fraction of PMN and monocytes but more equally distributed between the particulate fractions and cytosol of alveolar macrophages.