Hemoglobin potentiates oxidant injury in isolated rat lungs.

Abstract

Isolated perfused rat lungs were subjected to oxidant injury induced by tert-butyl hydroperoxide (t-buOOH), which caused a significant increase in capillary permeability as assessed by the change in the capillary filtration coefficient. t-buOOH caused an increase in the change in the capillary filtration coefficient (delta Kfc) of 0.27 +/- 0.05 ml.min.cmH2O-1.100 g lung tissue-1 (mean +/- SE) that was accompanied by an increase in thiobarbituric acid reactive products of lipid peroxidation in the lung perfusate. The addition of hemoglobin to the perfusate potentiated t-buOOH-induced lung injury as evidenced by a significantly greater (P = 0.007) delta Kfc of 0.43 +/- 0.05. t-buOOH also caused hemoglobin to release large quantities of free iron in vitro. The potentiation of t-buOOH-induced lung injury by hemoglobin was prevented by apotransferrin as evidenced by a significant reduction (P = 0.001) in delta Kfc to 0.13 +/- 0.02. No statistically significant (P greater than 0.05) changes in segmental resistances or pulmonary vascular pressures occurred in any of the lungs injured with t-buOOH when compared with time controls. These results demonstrate that t-buOOH causes an oxidant injury in isolated rat lungs that can be potentiated by free iron released from hemoglobin.

• Authors: A F Seibert, A E Taylor, J B Bass, J Haynes Jr
• Journal: The American journal of physiology (Am J Physiol) Vol. 260 Issue 6 Pt 2 Pg. H1980-4 (Jun 1991) ISSN: 0002-9513 [Print] United States
• PMID: 2058730 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Apoproteins
• Fenton's reagent
• Hemoglobins
• Membrane Lipids
• Peroxides
• Thiobarbiturates
• Transferrin
• apotransferrin
• tert-Butylhydroperoxide
• Hydrogen Peroxide
• Iron

Topics

• Animals
• Apoproteins (physiology)
• Capillary Permeability (drug effects)
• Hemodynamics (drug effects)
• Hemoglobins (metabolism, physiology)
• Hydrogen Peroxide (metabolism)
• In Vitro Techniques
• Iron (metabolism)
• Lipid Peroxidation
• Lung (drug effects, metabolism)
• Male
• Membrane Lipids (metabolism)
• Oxidation-Reduction
• Peroxides (adverse effects)
• Rats
• Thiobarbiturates (metabolism)
• Transferrin (physiology)
• tert-Butylhydroperoxide