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Published on: February 25, 2016
High nitric oxide production in human paranasal sinuses
J O Lundberg1, T Farkas-Szallasi, E Weitzberg
1Department of Physiology & Pharmacology, Karolinska Institute, Stockholm, Sweden.
Nature Medicine
|April 1, 1995
Summary
Nitric oxide (NO) is produced by human paranasal sinus epithelial cells at high concentrations. This finding suggests a role for NO in maintaining the sterility of the sinuses.
Area of Science:
- Respiratory physiology
- Immunology
- Biochemistry
Background:
- Nitric oxide (NO) is found in air from nasal airways, but its origin and function are unclear.
- High concentrations of NO have been detected in sinus air, nearing atmospheric pollution limits.
Purpose of the Study:
- To investigate the origin and physiological role of nitric oxide (NO) in the human paranasal sinuses.
- To determine the expression and activity of NO synthase in sinus and nasal epithelium.
Main Methods:
- Immunohistochemistry and mRNA in situ hybridization were used to localize NO synthase expression.
- NO synthase activity was measured in the sinus and nasal epithelium.
Main Results:
- Nitric oxide (NO) is constitutively expressed in the apical region of human paranasal sinus epithelium.
- NO synthase activity was significantly higher in sinus epithelium compared to nasal cavity epithelium.
- NO was found in very high concentrations in human sinus air.
Conclusions:
- The paranasal sinuses are a primary source of nitric oxide (NO) in the upper airway.
- Constitutive expression of NO synthase in sinus epithelium suggests a role in maintaining sinus sterility due to NO's bacteriostatic properties.
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