SUMMARY The role of cyclooxygenase in the mechanisms of vascular reactivity in the skin microcirculation of young healthy individuals Study aim: The aim of this study was to determine the role of cyclooxygenase enzyme in the physiological microcirculatory response to short-term flow disruption and the effect of n-3 PUFA and their metabolites, selenium, lutein and vitamin E on endothelial function of healthy young individuals who were consuming quatro-enriched chicken eggs. Structure of the study: The study was organized as randomized, double-blind, and placebo-controlled. Participants and methods: Subjects were divided into a control group, which consumed plain chicken eggs, and an experimental group, which consumed eggs enriched with n-3 PUFA, selenium, vitamin E, and lutein. The protocol lasted three weeks during which subjects consumed three boiled eggs per day. Before and after the protocol anthropological and hemodynamic measurements were performed alongside endothelial microcirculation assessment by laser Doppler flowmetry with acetylcholine iontophoresis and reactive hyperemia before and after oral administration of the nonselective cyclooxygenase inhibitor (indomethacin). Results: No significant differences were found in anthropological measurements before and after the protocol in both groups, while a significant difference was found in the values of systolic blood pressure and pulse in the control group after the protocol. No significant difference was found in acetylcholine-induced dilatation before and after the protocol in the experimental and control groups. A significant improvement in response to reactive hyperemia was found in the experimental group after the protocol. After administration of indomethacin in the experimental group after the protocol, there was a significant reduction in the response to reactive hyperemia. Conclusion: The results suggest a positive effect of consumption of eggs enriched with n-3 PUFA, selenium, lutein and vitamin E on the microvascular reactivity of healthy young subjects. The positive effect was also partially mediated by metabolites of the cyclooxygenase degradation pathway of n-3 PUFA.