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Updated: Jul 18, 2026
08:32
Application of Genetically Encoded Fluorescent Nitric Oxide (NO•) Probes, the geNOps, for Real-time Imaging of NO• Signals in Single Cells
Published on: March 16, 2017
Effects of nitric oxide on bovine polymorphonuclear functions
Véronique Boulanger1, Xin Zhao, Karoline Lauzon
1Dairy and Swine Research and Development Centre, PO Box 90, STN Lennoxville, 2000 College, Sherbrooke, Quebec J1M 1Z3.
Summary
Nitric oxide (NO) does not significantly impact bovine neutrophil function during inflammation. Studies show NO inhibition did not affect immune cell migration or pathogen destruction in mastitis models.
Area of Science:
- Veterinary Immunology
- Bovine Mastitis Research
- Nitric Oxide Biology
Background:
- Polymorphonuclear neutrophils (PMNs) are crucial for bovine immune response, particularly during mastitis.
- Nitric oxide (NO) is a signaling molecule with diverse roles in inflammation and immunity.
- The specific role of NO in bovine neutrophil function during infection remains incompletely understood.
Purpose of the Study:
- To investigate the effects of nitric oxide (NO) on the functionality of bovine polymorphonuclear neutrophils (PMNs) in milk and blood.
- To determine if inhibiting inducible nitric oxide synthase (iNOS) impacts PMN activity during experimentally induced mastitis.
- To assess the influence of NO on superoxide production and phagocytosis by bovine neutrophils.
Main Methods:
- Mastitis was induced in cows using Escherichia coli endotoxins.
- Aminoguanidine, an iNOS inhibitor, was administered to assess its effect on milk somatic cell counts and superoxide production.
- In vitro studies evaluated the impact of NO and iNOS inhibitors on superoxide production and bacterial phagocytosis by isolated bovine neutrophils and monocyte-neutrophil co-cultures.
Main Results:
- Aminoguanidine administration did not inhibit milk somatic cell counts or their superoxide production in mastitis models.
- In vitro, NO did not appear to be produced by bovine neutrophils.
- Neither NO derived from activated monocytes nor iNOS inhibitors affected superoxide release or bacterial phagocytosis by bovine neutrophils.
Conclusions:
- Inhibition of NO release does not interfere with bovine neutrophil migration or pathogen-destroying capabilities during inflammation.
- Nitric oxide (NO) does not seem to play a significant regulatory role in the function of bovine neutrophils.
- These findings suggest NO is not a primary mediator of bovine neutrophil responses in the context of mastitis.
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