Tetrahydrobiopterin, a critical factor in the production and role of nitric oxide in mast cells
- Mast cells (MC) are biologically potent, ubiquitously distributed immune cells with fundamental roles in host integrity and disease. MC diversity and function is regulated by exogenous nitric oxide; however, the production and function of endogenously produced NO in MC is enigmatic. We used rat peritoneal MC (PMC) as an in vivo model to examine intracellular NO production. Live cell confocal analysis of PMC using the NO-sensitive probe diaminofluorescein showed distinct patterns of intracellular NO formation with either antigen (Ag)/IgE (short term) or interferon-γ (IFN-γ) (long term). Ag/IgE-induced NO production is preceded by increased intracellular Ca2+, implying constitutive nitric-oxide synthase (NOS) activity. NO formation inhibits MC degranulation. NOS has obligate requirements for tetrahydrobiopterin (BH4), a product of GTP-cyclohydrolase I (CHI), IFN-γ-stimulated PMC increased CHI mRNA, protein, and enzymatic activity, while decreasing CHI feedback regulatory protein mRNA, causing sustained NO production. Treatment with the CHI inhibitor, 2,4-diamino-6-hydroxypyrimidine, inhibited NO in both IFN-γ and Ag/IgE systems, increasing MC degranulation. Reconstitution with the exogenous BH4 substrate, sepiapterin, restored NO formation and inhibited exocytosis. Thus, Ag/IgE and IFN-γ induced intracellular NO plays a key role in MC mediator release, and alterations in NOS activity via BH4 availability may be critical to the heterogeneous responsiveness of MC.
Author: | Mark Gilchrist, Christian HeßlingerGND, A. Dean BefusORCiD |
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URN: | urn:nbn:de:hebis:30:3-760738 |
DOI: | https://doi.org/10.1074/jbc.M307777200 |
ISSN: | 0021-9258 |
Pubmed Id: | https://pubmed.ncbi.nlm.nih.gov/14514683 |
Parent Title (English): | Journal of biological chemistry |
Publisher: | American Society for Biochemistry and Molecular Biology Publications |
Place of publication: | Bethesda, Md |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2021/01/04 |
Year of first Publication: | 2003 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2024/02/03 |
Volume: | 278.2003 |
Issue: | 50 |
Page Number: | 8 |
First Page: | 50607 |
Last Page: | 50614 |
Institutes: | Medizin |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 57 Biowissenschaften; Biologie / 570 Biowissenschaften; Biologie |
6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit | |
Sammlungen: | Universitätspublikationen |
Licence (German): | Creative Commons - CC BY - Namensnennung 4.0 International |