Aspartate aminotransferase increases in crevicular fluid during experimental periodontitis in beagle dogs.

A ligature-induced periodontitis model employing the beagle dog was used to study the levels of aspartate aminotransferase (AST) in crevicular fluid before and after ligation. A significant increase in AST level occurred in crevicular fluid 2 weeks after ligation whereas no increase of enzyme was found in serum. Enzyme levels in crevicular fluid were 10- to 100-fold higher than in serum. Dental plaque did not appear to be the source of the enzyme. Since aspartate aminotransferase has been documented as a marker of cellular injury arising during heart disease and liver disease, this study suggests that aspartate aminotransferase, in like fashion, reflects cellular damage arising from active periodontal disease.