  Understanding stress-strain relationships in arteries is important for
fundamental investigations in mechanobiology. Here we demonstrate the essential
role of chemoelasticity in determining the mechanical properties of arterial
tissues. Stepwise stress-relaxation uniaxial tensile tests were carried out on
samples of porcine thoracic aortas immersed in a hyperosmotic solution. The
tissue deformations were tracked using optical coherence tomography (OCT)
during the tensile tests and digital volume correlation (DVC) was used to
obtain measurements of depth-resolved strains across the whole thickness of the
tested aortas. The hyperosmotic solution exacerbated chemoelastic effects, and
we were able to measure different manifestations of these chemoelastic effects:
swelling of the media inducing a modification of its optical properties,
existence of a transverse tensile strain. For the first time ever to our best
knowledge, 3D strains induced by chemoelastic effects in soft tissues were
quantified thanks to the OCT-DVC method. Without doubt, chemoelasticity plays
an essential role in arterial mechanobiology in vivo and future work should
focus on characterizing chemoelastic effects in arterial walls under
physiological and disease conditions. Statement of significance:
Chemoelasticity, coupling osmotic phenomena and mechanical stresses, is
essential in soft tissue mechanobiology. For the first time ever, we measure
and analyze 3D strain fields induced by these chemoelastic effects thanks to
the unique combination of OCT imaging and digital volume correlation.
