Abstract
The epoxy group of the epoxy compounds has an oxygen arm which can work as a flexible joint in a cross-linking bridge, and can block not only amino group but also carboxy group of collagen peptide. The purpose of this study is to evaluate the anticalcification efficacy of the epoxy compounds as a cross-linking agent for xenograft bioprostheses. Porcine aortic leaflets were treated with 2% epoxy compounds (glycerol polyglycidyl ether; EX-314) and implanted in subctuaneous layer of 4-week rats. Measurement of calcium content showed that epoxy-treated implants received a minimal calcification: mean 0.64 μg/mg dry weight leaflet tissue (range 0.5-0.8; N=7) at 1 month; mean 0.94 μg/mg (range 0.3-1.3; N=9) at 2 months; and mean 1.2μg/mg (range 0.5-2.1; N=10) at 3 moths. Natural leaflets contained calcium of mean 0.43μg/mg. By contrast, 0.625% glutaraldehyde-preserved implants were severely calcified: mean 102μg/mg (range 41-130; N=14) at 1 month; mean 139μg/mg (reange 73-205; N=20) at 2 months; and mean 170μg/mg (range 90-214; N=20) at 3 months. It is concluded that the epoxy compounds provide the more pronounced anticalcification effects than does the glutaraldehyde under the pressure and volume loadfree subcutaneous circumstances.
