Responses of rabbit pulmonary arteries to hydrogen peroxide

Conference · Fri Mar 15 00:00:00 EST 1991 · FASEB Journal (Federation of American Societies for Experimental Biology); (United States)

OSTI ID:5212887

Russell, J A; Gugino, S F; Giese, E C ^[1]

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1. State Univ. of New York, Buffalo (United States)

The effects of hydrogen peroxide on isolated rabbit intrapulmonary arteries were investigated using tissue bath techniques. Exposure of resting vessels to 10{sup {minus}7}-10{sup {minus}5} M H{sub 2}O{sub 2} caused concentration-dependent contractions that were blocked by 10{sup {minus}5} M indomethacin, 3 {times} 10{sup {minus}6} M SQ 29548 or by removal of the endothelium. Addition of a single concentration of H{sub 2}O{sub 2} to resting vessels incubated with 3 {times} 10{sup {minus}6} M SQ 29548 caused slowly developing contractions that attained approximately 80% of the response to 118mM KCL. Late phase contractions were highly resistance to the inhibitory effects of 10{sup {minus}8}-10{sup {minus}5} M isoproterenol or 10{sup {minus}7}-10{sup {minus}5} M sodium nitroprusside and they persisted in calcium-free media, in vessels incubated with 5 {times} 10{sup {minus}5} M verapamil, and after removal of the endothelium. Pulmonary arteries incubated with 3 {times} 10{sup {minus}6} M SQ 29548 and contracted by 10{sup {minus}7} M phenylephrine relaxed in response to 10{sup {minus}7}-10{sup {minus}5} M H{sub 2}O{sub 2}. H{sub 2}O{sub 2}-induced relaxations were unaffected by 10{sup {minus}4} M N{omega}-nitro-L-arginine or 10{sup {minus}5}M indomethacin but were partially depressed by removal of the endothelium. The authors conclude that H{sub 2}O{sub 2} causes: an early phase contraction via release of thromboxane A2 from endothelial cells; a late-phase contraction that is endothelium-independent and probably results from the release of calcium from intracellular stores in smooth muscle cells; and an early phase relaxation that may be due to both endothelium-dependent and endothelium-independent mechanisms. The endothelium-derived relaxing factor does not appear to be nitric oxide or a dilator prostaglandin.

• OSTI ID: 5212887
• Report Number(s): CONF-9104107-; CODEN: FAJOE
• Journal Information: FASEB Journal (Federation of American Societies for Experimental Biology); (United States), Vol. 5:5; Conference: 75. annual meeting of the Federation of American Societies for Experimental Biology (FASEB), Atlanta, GA (United States), 21-25 Apr 1991; ISSN 0892-6638
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
HYDROGEN PEROXIDE
BIOLOGICAL EFFECTS
MUSCLES
CONTRACTION
ARTERIES
DOSE-RESPONSE RELATIONSHIPS
ENDOTHELIUM
ENZYME INHIBITORS
LUNGS
RABBITS
ANIMAL TISSUES
ANIMALS
BLOOD VESSELS
BODY
CARDIOVASCULAR SYSTEM
HYDROGEN COMPOUNDS
MAMMALS
ORGANS
OXYGEN COMPOUNDS
PEROXIDES
RESPIRATORY SYSTEM
TISSUES
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology