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Updated: Jun 3, 2026
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En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries
Published on: February 25, 2016
Nitric oxide synthases in varicose vein wall
Z Haviarova1, A Janegova, P Janega
1Institute of Anatomy, Medical Faculty, Comenius University, Bratislava, Slovakia. zora.haviarova@fmed.uniba.sk
Bratislavske Lekarske Listy
|April 2, 2011
Summary
Varicose veins show reduced expression of nitric oxide synthase (NOS) isoforms in the vein wall. This suggests lower nitric oxide (NO) levels, indicating varicose vasodilation may occur through different mechanisms.
Area of Science:
- Vascular Biology
- Biochemistry
Background:
- Primary varicose veins are linked to venous wall weakness, but structural changes remain debated.
- Nitric oxide (NO), a vasodilator, is synthesized by nitric oxide synthase (NOS), with three isoforms: nNOS, iNOS, and eNOS.
Purpose of the Study:
- To investigate the expression of all three NOS isoforms in varicose veins compared to healthy controls.
- To explore the role of NOS and NO in the pathophysiology of varicose veins.
Main Methods:
- Standard light microscopy and immunohistochemistry were used on 10 varicose and 10 control vein samples.
- Antibody expression for iNOS, eNOS, and nNOS was evaluated semiquantitatively and morphometrically using 2D image analysis.
Main Results:
- A discontinuous and significantly lower expression of all three NOS isoforms was observed in the tunica media of varicose veins compared to controls.
- Control veins exhibited continuous expression of all three NOS isoforms.
Conclusions:
- The findings suggest lower NO levels in varicose vein walls, implying vasodilation may involve mechanisms other than NO.
- These results contrast with previous studies reporting elevated NO levels in severe chronic venous disease.
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