Age-related changes of skin blood flow during postocclusive reactive hyperemia in human

Background/Purpose: The objective was to study age-related alterations in the time-amplitude characteristics of the oscillatory components of peripheral blood flow in healthy humans during postocclusive reactive hyperemia. Methods: Forearm blood skin perfusion was studied by the method of laser Doppler flowmetry in 120 healthy volunteers, who were divided into two age groups: young (19-30 years old; n = 82) and middle-age (30-60 years old; n = 38). The forearm occlusion approach was used to reveal the reaction of the microvascular bed to transient ischemia. To estimate the age-related changes of separate oscillatory components of LDF signals during postocclusive reactive hyperemia, we applied adaptive time-amplitude wavelet analysis. Results: A statistically significant increase in the skin blood perfusion after occlusion removal was revealed: 4-fold in the 1st and 3.5-fold in the 2nd group respectively. Both the amplitude of blood flow oscillations at rest and the postocclusive growth of the amplitude showed an age-related decline in the frequency intervals associated with the myogenic (0.052-0.145 Hz), sympathetic (0.021-0.052 Hz) and endothelial (0.0095-0.021 Hz) activity. Conclusion: The time-amplitude characteristics of the oscillatory components of peripheral blood flow depend on age, with the dependence becoming more evident after a transient ischemia.