Figure 3. Transient endothelial dysfunction induced by periodontitis. Ligature rats were prepared for mean arterial pressure recording 1 h (day 0), 14 days, or 21 days after the procedure. Increasing doses of acetylcholine (A) or sodium nitroprusside (B) were injected, and the change in mean arterial pressure (% of decrease from basal blood pressure) was determined. The basal mean arterial pressure is also shown (C). Statistical analysis was performed using one-way analysis of variance followed by Bonferroni post hoc test. **p<0.01 and *** p<0.001.