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This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Rights and Permissions Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Choury, D. Articles by Kaplan, J. C. Search for Related Content PubMed PubMed Citation Articles by Choury, D. Articles by Kaplan, J. C. Social Bookmarking                   What's this?  Previous Article  |  Table of Contents  |  Next Article  Endogenous proteolysis of membrane-bound red cell cytochrome-b5 reductase in adults and newborns: its possible relevance to the generation of the soluble "methemoglobin reductase" D Choury, A Reghis, AL Pichard and JC Kaplan The problem of the low activity of so-called methemoglobin reductase in red cells from newborns was reinvestigated in view of our current knowledge of this enzyme, i.e., (1) its being cytochrome-b5 reductase and (2) its presence in two forms: soluble and membrane-bound. We found that red cells from cord blood and newborns exhibited a 50% decrease of soluble cytochrome-b5 reductase activity, whereas membrane-bound activity was in the adult range. Ghosts from these cells possessed diminished ability to solubilize membrane-bound cytochrome-b5 reductase in the course of in vitro auto-incubation. This autosolubilizing ability increased with age and reached adult level concomitantly with soluble cytochrome-b5 reductase activity at 6 mo. We conclude that the relative deficiency of soluble cytochrome-b5 reductase observed at birth is due to diminished post-translational processing of the membrane-bound enzyme during erythropoiesis of fetal cells. This processing is calcium-dependent related to calmodulin. Volume 61, Issue 5, pp. 894-898, 05/01/1983 Copyright © 1983 by The American Society of Hematology CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this? This article has been cited by other articles: R. K. Anand and E. Appachi Case Report of Methemoglobinemia in Two Patients with Food Protein-Induced Enterocolitis Clinical Pediatrics, September 1, 2006; 45(7): 679 - 682. [PDF]

	Copyright © 1983 by American Society of Hematology         Online ISSN: 1528-0020