Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1987 Feb 15;242(1):103-7.
doi: 10.1042/bj2420103.

The inhibition by diphenyleneiodonium and its analogues of superoxide generation by macrophages

The inhibition by diphenyleneiodonium and its analogues of superoxide generation by macrophages

J T Hancock et al. Biochem J. .

Abstract

Peritoneal macrophages were elicited in rats by using casein as a stimulus; when stimulated with phorbol 12-myristate 13-acetate (PMA) they produced O2.-. Nearly 60% of the total cytochrome b had a low Em,7.0 of -247 mV, typical of the cytochrome b component found in the NADPH-dependent O2(.-)-generating oxidase of neutrophils. The rate of O2.- generation by macrophages was 1.23 mol of O2.-/s per mol of cytochrome b. Treatment of intact macrophages with diphenyleniodonium (DPI) at 0.9 microM caused 50% inhibition of PMA-induced O2.- generation, with little effect on mitochondrial respiratory activity; KCN inhibited respiratory activity without affecting PMA-induced O2.- generation. A similar specificity of inhibition was found for di-2-thienyliodonium (50% inhibition of O2.- generation at 0.5 microM) and, at higher concentrations, for diphenyl iodonium. When macrophage suspensions were incubated with [125I]DPI followed by autoradiography of SDS/polyacrylamide-gel-electrophoresis-separated polypeptides, radioactivity was most strongly associated with a band of Mr 45,000, similar to that found in neutrophils [Cross & Jones (1986) Biochem. J. 237, 111-116]. The O2(.-)-generating oxidase of macrophages appears to have components in common with the NADPH oxidase of neutrophils, despite differences in activity. Its sensitivity to DPI suggests that selective prevention of radical generation by macrophages in vivo is possible.

PubMed Disclaimer

Similar articles

Cited by

References

    1. Biochem J. 1976 Aug 15;158(2):307-15 - PubMed
    1. Anal Biochem. 1976 May 7;72:248-54 - PubMed
    1. J Exp Med. 1978 Jul 1;148(1):115-27 - PubMed
    1. Biochem Soc Trans. 1979 Feb;7(1):103-6 - PubMed
    1. Biochemistry. 1981 Mar 17;20(6):1468-76 - PubMed

Publication types

-