PTGS2 and ulcer disease: Quantification of the immunopositive areas for the COX isoforms revealed reduced expression of COX-1 (28.5%, P < 0.05), and COX-2 (37.6%, P < 0.01) in the ulcerated untreated mice on the day of ulcer induction itself, compared to normal mice (Fig. 2 and Fig. 3).