CHARACTERIZATION OF HUMAN AORTIC COLLAGENS ELASTICITY BY NUCLEAR-MAGNETIC-RESONANCE

The elasticity of the human aortic wall in longitudinal uniaxial elong ation at high strain, known to be determined mostly from tissular coll agen's behaviour, is studied and compared to the second moment of the H-1 nuclear magnetic resonance (NMR) solid state line-shape, a proton nuclear magnetic resonance (at 60 MHz) characteristic for the molecula r motion and the rigidity of the collagen macromolecular backbone. The H-1 NMR signal of collagen is identified after selective histological ly controlled chemical lysis. The computed second moment of the line-s hape shows statistically significant correlation with the slope of the strain-stress curve of the aorta at high strain, thus proving the rel ationship between a macroscopic tissular elasticity parameter and a ma cromolecular rigidity characteristic of collagen, a major tissular com ponent. In vivo extension of this technique (e.g., MRI) would allow us to gain information on the biomechanical state of the aorta, a natura lly highly stressed and strained tissue.