A new vacuum-operated stress-providing instrument that applies static or variable duration cyclic tension or...

An instrument providing cyclic stress to cells cultured in vitro has been developed. The unit uses a vacuum to deform a plastic Petri dish yielding 0.13% compression to cells on the inner surface, measured by strain gauge recordings. A regimen of 25 s stress and 5 min relaxation induced no significant change in synthesis of a 45 X 10(3) Mr protein that comigrates with actin, whereas a 52 X 10(3) Mr protein that comigrated with tubulin decreased from 12.7 +/- 0.451% of the total protein synthesized in control, static cells to 8.53 +/- 0.182% in stressed cells. The unit may have a broad application in monitoring biochemical changes in response to stress in cells such as muscle, lung, tendon, ligament and bone that are normally subjected to tension or compression.