An equibiaxial strain system for cultured cells.
We developed a device that applies homogeneous equibiaxial strains of 0-10% to a cell culture substrate and quantitatively verified transmission of substrate deformation to cultured cardiac cells. Clamped elastic membranes in both single-well and multiwell versions of the device are uniformly stretched by indentation with a plastic ring, resulting in strain that is directly proportional to the pitch-to-radius ratio. Two-dimensional deformations were measured by tracking fluorescent microspheres attached to the substrate and to cultured adult rat cardiac fibroblasts. For nominal stretches up to 18%, strains along circumferential and radial axes were equal in magnitude and homogeneously distributed with negligible shear. For 5% stretch, circumferential and radial strains in the substrate were 0.046 +/- 0.005 and 0.048 +/- 0.004 [not significant (NS)], respectively, and shear strain was 0.001 +/- 0.003 (NS). Calibration of both single-well and multiwell versions permits strain selection by device rotation. The reproducible application and quantification of homogeneous equibiaxial strain in cultured cells provides a quantitative approach for correlating mechanical stimuli to cellular transduction mechanisms.
Department of Bioengineering and Medicine, University of California at San Diego, USA.
A A
AA
Lee
T
T
Delhaas
L K
LK
Waldman
D A
DA
MacKenna
F J
FJ
Villarreal
A D
AD
McCulloch
D000818:Animals; D002478:Cells, Cultured; D004548:Elasticity; D006321:Heart / Q000502:physiology*; D009206:Myocardium / Q000166:cytology*; D051381:Rats; D013314:Stress, Mechanical