Isolation of purified insoluble aortic collagen

The chemistry of collagen from major blood vessels, such as the aorta, is poorly defined because of problems encountered in solubilization techniques. Normal extraction of calf aorta with acetic acid and/or pepsin does not yield significant quantities of collagen. However, treatment of the aorta with purified pancreatic elastase results in a residue containing a significant portion of the collagen. The amino acid analysis, the acrylamide gel electrophoretic patterns and the electron micrographs of this residue display characteristics consistent with relatively pure collagen. Using this purified collagen preparation approximately 90% of the collagenous material present can be solubilized by pepsin treatment.