Chronic vibrations constrict vessels
By Janet Raloff
Many people who work with vibrating power tools develop a syndrome that starts with pain and evolves to include tingling or numbness and sensitivity to cold. Researchers at the Medical College of Wisconsin in Milwaukee think they’ve discovered a key effect of the vibrations: combined squeezing and twisting of arterial cells to the breaking point.
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Sandya Govindaraju and her colleagues worked with rats, in which the tail artery is comparable to the arteries in people’s fingers. The researchers vibrated the rodents’ tails for 5 minutes to 4 hours at 60-hertz frequencies.