Differential Inhibition by Iodonium Compounds of Induced Erythropoietin Expression

doi:10.1074/jbc.270.6.2628

Differential Inhibition by Iodonium Compounds of Induced Erythropoietin Expression (*)

From the Department of Biochemistry and Molecular Biology, the University of Chicago, Chicago, Illinois 60637

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Abstract

Diphenylene iodonium chloride suppresses the cobaltous chloride-induced expression of erythropoietin by Hep3B cells to about 50% at a concentration of 30 nM. At that concentration, it has no effect on the response to low oxygen. The related compound iodonium diphenyl chloride acts similarly but is a much less effective inhibitor.

If, as reported, diphenylene iodonium chloride is a specific inhibitor of cytochrome b, it follows that the response to CoCl₂ is dependent on that enzyme but the response to hypoxia is not.

Footnotes

↵* This work was supported in part by National Institutes of Health Grants HL21676 and HL30121. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore by hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
↵¹ The abbreviations used are:

epo

erythropoietin

DPI

diphenylene iodonium chloride

IDP

iodonium diphenyl chloride.
- Received October 27, 1994.