Characterization of frequency-dependent responses of the vascular system to repetitive vibration.

Abstract

The current frequency weighting proposed in the International Standards Organization-5349 standard may underestimate the risk of injury associated with exposure to vibration >100 Hz. The goal of this study was to assess the frequency-dependent responses of the peripheral vascular system to repeated bouts of vibration. The effects of exposure to vibration at 62.5, 125, or 250 Hz (constant acceleration of 49 m/s2) on vascular morphology, oxidative stress, inflammation, and gene expression were examined in the ventral tail artery of rats. Vascular responses indicative of dysfunction (eg, remodeling and oxidative activity) became more pronounced as the frequency of the exposure increased. Exposure to vibration frequencies that induce the greatest stress and strain on the tail (ie, >100 Hz) result in vascular changes indicative of dysfunction.