Effects of a β2-adrenergic receptor blocker on experimental periodontitis in spontaneously hypertensive rats.

Recent studies have reported a relationship between periodontal disease and hypertension, and previous evidence suggests that the sympathetic nervous system plays an important role in the control of bone metabolism. This study sought to evaluate the effect of the beta-2 adrenergic receptor (β2-AR) blocker butoxamine on experimental periodontitis in a rat model. Wistar-Kyoto and spontaneously hypertensive rats (n = 6 per group) were orally administered butoxamine 1 mg/kg/day and experimental periodontitis was induced by applying an orthodontic ligature wire. The rats were sacrificed after 4 weeks and the residual alveolar bone was measured using micro-computed tomography (micro-CT) imaging analysis software for histological analysis. Micro-CT imaging analysis showed a higher ratio of residual alveolar bone, BV/TV, and Tb.N in both Wistar-Kyoto and spontaneously hypertensive rats treated with butoxamine compared with the corresponding control rats. In histological analysis, compared with the Wistar-Kyoto and spontaneously hypertensive rat control groups, the corresponding butoxamine-treated groups showed a lower ratio of attachment level, lower values of osteoclast number and surface. β2-AR blockers maintained the alveolar bone mass and attachment level by suppressing osteoclast activity. Thus, β2-AR blockers may be effective in preventing periodontitis. • β2-AR blockers suppressed the expression of the cytokines TNF-α, IL-1β, and IL-6. • β2-AR blockers suppressed the activity of osteoclasts and sympathetic nerve fibers. • β2-AR blockers maintained alveolar bone mass and attachment level. • β2-AR blockers may be effective in preventing periodontitis. • Sympathicotonia is associated with increased severity of periodontitis. [ABSTRACT FROM AUTHOR]