Superoxide radicals stimulate IP sub 3 -induced Ca sup 2+ -release from vascular smooth muscle sarcoplasmic reticulum

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

OSTI ID:5145083

Ford, G D; Suzuki, Y ^[1]

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1. Medical College of Virginia, Richmond (United States)

Oxygen free radicals have been implicated in a variety of pathophysiological conditions and vascular smooth muscle can be a site of damage in such oxygen toxicity. Mechanisms of the effects of these radials on the vascular smooth muscle at the cellular level, however, have not been well studied. In the present study, the authors report that the inositol 1,4,5-trisphosphate (IP{sub 3})-induced Ca{sup 2+}-release from bovine aortic SR was also affected by O{sub 2}{sup {minus}}. Hypoxanthine plus xanthine oxidase in the presence of catalase stimulated the IP{sub 3}-induced Ca{sup 2+}-release from SR monitored using arsenazo III. At 10 {mu}M IP{sub 3}, the release was doubled by O{sub 2}{sup {minus}} treatment. As a consequence of using higher SR protein concentrations required to observe the Ca{sup 2+}-uptake inhibition induced by O{sub 2}{sup {minus}}. Since the effect of O{sub 2}{sup {minus}} was not seen when a non-hydrolyzable analogue of IP{sub 3} is used to induce Ca{sup 2+}-release, O{sub 2}{sup {minus}} may be inhibiting the degradation processes of IP{sub 3} rather than having an influence on the release channel per se.

• OSTI ID: 5145083
• 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

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63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CALCIUM COMPOUNDS
SECRETION
PHOSPHOLIPIDS
BIOCHEMICAL REACTION KINETICS
SUPEROXIDE RADICALS
BIOLOGICAL EFFECTS
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ENZYMES
ESTERS
KINETICS
LIPIDS
MAMMALS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANS
PROTEINS
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560300* - Chemicals Metabolism & Toxicology