Induction of pulmonary metallothionein following oxygen exposure.
Metallothionein (MT) levels were measured by radioimmunoassay in lungs of animals exposed 0, 3, and 6 days to 85% oxygen. MT levels increased with duration of exposure from 112.0 ng/lung in sham air control animals to 872.6 ng/lung in animals exposed for 6 days to oxygen. Gel chromatographic analysis of lung homogenates from oxygen-exposed animals revealed the presence of a copper- and zinc-binding component with an approximate molecular weight of 12,000 Da. It was heat stable and cross-reacted with anti-MT. The induction of pulmonary Cu/Zn-thionein was accompanied by an acute phase response, characterized by elevated serum Cu and ceruloplasmin levels and depressed serum Zn. Total lung Cu and Zn also increased, perhaps as a consequence of normal repairative processes necessitated by the oxidant injury. Increased adrenal weight and coincident thymic atrophy in oxygen-exposed animals suggested the participation of adrenocorticosteroids in the induction process.
Hart
B A
BA
Department of Biochemistry, University of Vermont College of Medicine, Burlington 05405.
Voss
G W
GW
Garvey
J S
JS
D000818:Animals; D002352:Carrier Proteins / Q000032:analysis; D002570:Ceruloplasmin / Q000032:analysis; D003300:Copper / Q000032:analysis / Q000097:blood; D008168:Lung / Q000032:analysis / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008668:Metallothionein / Q000032:analysis / Q000378:metabolism* / Q000502:physiology; D010088:Oxidoreductases / Q000378:metabolism; D010100:Oxygen / Q000494:pharmacology*; D011863:Radioimmunoassay; D051381:Rats; D011917:Rats, Inbred Lew; D013997:Time Factors; D015032:Zinc / Q000032:analysis / Q000097:blood
D002352:Carrier Proteins; C023548:copper-binding protein; C017800:zinc-binding protein; D003300:Copper; D008668:Metallothionein; D010088:Oxidoreductases; D002570:Ceruloplasmin; D015032:Zinc; D010100:Oxygen