THE EFFECT OF SHEAR-STRESS ON FIBROBLASTS DERIVED FROM DUPUYTRENS TISSUE AND NORMAL PALMAR FASCIA

This study examines the real-time intracellular calcium changes of pal mar fascia from normal and Dupuytren's diseased fibroblasts in respons e to shear stress. The real-rime cytosolic calcium changes were measur ed using fluorescence microscopy image processing. The preconfluent pr imary cultured cells were exposed to 1 minute of flow at 25 dyne/cm(2) after a 2-minute baseline of no flow. Additionally, the cells were ex posed to an influx of Hank's buffered saline solution with 2% newborn bovine serum to examine the response to serum-born (chemical) agonists . Cytosolic calcium changes were measured as the percentage change ove r the 2-minute baseline of the mean [Ca2+]i peak. The mean change of t he peak [Ca2+]i response of the normal palmar fascia was significantly greater than that of the cells from the Dupuytren's nodular and perin odular tissue. The response to the chemical agonist showed a robust bu t not statistically different response between the 3 cell types. Our w ork supports the hypothesis that palmar fascia responds to mechanical stress, specifically laminar fluid flow. These findings may help to ex plain that an underlying abnormality in the cells of the palmar fascia may be expressed by exposure to laminar fluid flow, a physical signal , rather than a chemical agonist. Copyright (C) 1998 by the American S ociety for Surgery of the Hand.