Effects of endotoxin on neutrophil-mediated I/R injury in isolated perfused rat hearts.

Abstract

With the use of a syngeneic model, we demonstrate that rat polymorphonuclear neutrophils (PMNs) exacerbate ischemia-reperfusion injury in the isolated rat heart. However, PMNs (19 x 10(6) cells) from lipopolysaccharide (LPS)-treated rats (LPS-PMNs; 100 mg/kg administered 7 h before exsanguination) induce less reperfusion injury in the isolated heart. Average recovery of left ventricular developed pressure after 20 min of ischemia and 60 min of reperfusion was 51 +/- 4% in hearts receiving PMNs from saline-treated control rats (saline-PMNs) versus 78 +/- 2% in hearts receiving LPS-PMNs. Ischemic hearts reperfused with LPS-PMNs recovered to the same extent as did hearts reperfused with Krebs buffer only. LPS-PMNs and saline-PMNs showed no difference in basal or phorbol ester-induced superoxide production. Whereas twice the number of LPS-PMNs was positive for nitroblue tetrazolium, the percent positive for L-selectin, a receptor integral in PMN-adhesion to endothelium, was 50% less in LPS-PMNs than in controls. After reperfusion, three-fourths of the saline-PMNs remained within the hearts, whereas only one-fourth of LPS-PMNs were trapped. These data suggest that PMNs from LPS-treated rats do not exacerbate ischemia-reperfusion injury as do control PMNs, possibly, due to impaired PMN adhesion to endothelium as a result of decreased L-selectin receptors.

• Authors: B P Lipton, A P Bautista, J B Delcarpio, K H McDonough
• Journal: American journal of physiology. Heart and circulatory physiology (Am J Physiol Heart Circ Physiol) Vol. 280 Issue 2 Pg. H802-11 (Feb 2001) ISSN: 0363-6135 [Print] United States
• PMID: 11158980 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Carcinogens
• Lipopolysaccharides
• L-Selectin
• Malondialdehyde
• Adenosine Triphosphate
• L-Lactate Dehydrogenase
• Tetradecanoylphorbol Acetate

Topics

• Adenosine Triphosphate (analysis)
• Animals
• Carcinogens (pharmacology)
• Cell Adhesion (immunology)
• Diastole (drug effects, immunology)
• Endothelium, Vascular (cytology, immunology)
• In Vitro Techniques
• L-Lactate Dehydrogenase (analysis)
• L-Selectin (analysis)
• Lipopolysaccharides (pharmacology)
• Male
• Malondialdehyde (analysis)
• Myocardial Reperfusion Injury (immunology)
• Myocardium (enzymology)
• Neutrophils (chemistry, drug effects, immunology)
• Perfusion
• Rats
• Rats, Sprague-Dawley
• Systole (drug effects, immunology)
• Tetradecanoylphorbol Acetate (pharmacology)
• Ventricular Function, Left (drug effects, immunology)
• Ventricular Pressure (drug effects, immunology)