Local and cardiorenal effects of periodontitis in nitric oxide-deficient hypertensive rats

Abstract Objective In this study we have assessed the renal and cardiac consequences of ligature-induced periodontitis in both normotensive and nitric oxide (NO)-deficient (L-NAME-treated) hypertensive rats. Materials and methods Oral L-NAME (or water) treatment was started two weeks prior to induction of periodontitis. Rats were sacrificed 3, 7 or 14 days after ligature placement, and alveolar bone loss was evaluated radiographically. Thiobarbituric reactive species (TBARS; a lipid peroxidation index), protein nitrotyrosine (NT; a marker of protein nitration) and myeloperoxidase activity (MPO; a neutrophil marker) were determined in the heart and kidney. Results In NO-deficient hypertensive rats, periodontitis-induced alveolar bone loss was significantly diminished. In addition, periodontitis-induced cardiac NT elevation was completely prevented by L-NAME treatment. On the other hand L-NAME treatment enhanced MPO production in both heart and kidneys of rats with periodontitis. No changes due to periodontitis were observed in cardiac or renal TBARS content. Conclusions In addition to mediating alveolar bone loss, NO contributes to systemic effects of periodontitis in the heart and kidney.