Abstract | OBJECTIVE: To determine whether or nor iron affects the depolarizing activity of a circulating shock protein that appears in plasma after hemorrhage. DESIGN: Randomized design. SETTING: University laboratory. ANIMALS: Healthy male Sprague-Dawley rats weighing 300 to 400 g with femoral artery and vein cannulas placed 4 days before hemorrhage. INTERVENTION: MAIN OUTCOME MEASURES: Depolarizing activity was measured as the increased fluorescence of an oxonol dye in the presence of Fe3+, Fe2+, or the iron chelator deferoxamine mesylate and was titrated against increasing concentrations of circulating shock protein or iron. Circulating shock protein was derived from plasma and was purified in two steps: stepwise ammonium sulfate precipitation followed by denaturing ion-exchange chromatography and refolding. RESULTS: At physiologic concentrations, Fe3+ but not Fe2+ potentiated the depolarizing activity of plasma after ammonium sulfate. Addition of deferoxamine abolished activity. Denaturing chromatography removed nearly all the depolarizing activity; however, Fe3+ restored activity to this fraction. Fe3+ increased total activity and decreased the concentration at which 50% activity was observed. CONCLUSION: These data indicate that physiologic concentrations of Fe3+ may act to modulate the depolarizing activity of circulating shock protein that in turn mediates the intracellular accumulation of salt and water in shock.
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Authors | B J Eastridge, J A Evans, D N Darlington, D S Gann |
Journal | Archives of surgery (Chicago, Ill. : 1960)
(Arch Surg)
Vol. 129
Issue 3
Pg. 245-51
(Mar 1994)
ISSN: 0004-0010 [Print] United States |
PMID | 8129597
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Ferric Compounds
- Ferrous Compounds
- Flavoproteins
- Heat-Shock Proteins
- Pyridoxal Phosphate
- Deferoxamine
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Topics |
- Animals
- Deferoxamine
(pharmacology)
- Dose-Response Relationship, Drug
- Electrophysiology
- Erythrocyte Membrane
(drug effects)
- Ferric Compounds
(pharmacology)
- Ferrous Compounds
(pharmacology)
- Flavoproteins
(pharmacology)
- Heat-Shock Proteins
(blood, drug effects, physiology)
- Hemorrhage
(blood)
- Male
- Pyridoxal Phosphate
(pharmacology)
- Random Allocation
- Rats
- Rats, Sprague-Dawley
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