Figure 5. Effect of selective COX inhibitors in the compensatory response to acetylcholine-induced hypotension during periodontitis. Twenty-one days after ligature procedure, the animals were prepared for blood pressure recording and a dose response curve to acetylcholine was performed. Then, SC-560 (selective COX-1 inhibitor; 2 mg/kg; i.v; A), NS-398 (selective COX-2 inhibitor; 2 mg/kg; i.v; B) or NS-398 plus SC-560 (both 2 mg/kg; i.v.; C) were injected. After 30 minutes, a second dose response curve to acetylcholine was obtained. The change of mean arterial pressure (% of decrease from basal blood pressure) was calculated. Statistical analyses were performed using Student's t test for paired samples.