Biomechanical Characterization of the Carotid Artery in Lambs Exposed to Chronic Hypoxia

Abstract

The mechanical characterization of arteries is a topic of interest, as it allows for the determination of vascular function and responses to clinical treatments. A study of arterial biomechanics presents difficulties and challenges, as complex aspects of their behavior must be considered, such as hyperelasticity, anisotropy, viscous effects, and the presence of residual stresses, among others. The objective of this work is to study the passive biomechanical response of carotid arteries through uniaxial tensile tests in axial and circumferential directions, measurement of pre-stretch, opening angles, and histomorphometric quantifiers, with the purpose of evaluating the effects of melatonin treatment administered to lambs gestated and born in hypobaric hypoxia (>2500 meters above sea level). In biomechanical characterization, the Gasser-Holzapfel-Ogden constitutive model (2006) is used, which is hyperelastic and anisotropic, because it includes the contribution of two families of fibers within the arterial matrix. The evaluation of biomechanical and histomorphometric changes contributes to the biomedical field in search of treatment for vascular problems observed at high altitudes, where hypobaric hypoxia is present.