X-ray diffraction and scanning electron microscopy of bovine media aortic wall

Scanning electron microscopy and high angle X-ray diffraction were used to define the relationship between collagen and elastin of bovine aortic wall. The diffraction pattern shows on one hand that the broad rings at 4.5 A and 9 A, due to elastin, do not orient on stretching and on the other hand, that the collagen rings at 11 A and 2.9 A start to orient at low elongations. These data together with scanning electron microscopy suggest a tight structural relationship between collagen and elastin that should influence the mechanics of deformation at all degrees of elongation.