Figure 3 Expression and dynamics of cyclooxygenases (COXs) and prostaglandin E synthase (PGES) in rat oesophagitis. Western blotting (A) showed that COX‐2 and microsomal PGES (mPGES)‐1 expression was significantly increased in rat oesophagitis while modest changes in COX‐1, cytosolic PGES (cPGES), and mPGES‐2 expression were observed. Real time reverse transcription‐polymerase chain reaction (RT‐PCR) (B) revealed that expression of COX‐2, cPGES, and mPGES‐1 mRNA but not mPGES‐2 mRNA was significantly increased compared with normal oesophagus, with a particularly marked increase in COX‐2 mRNA expression observed. Relative mRNA levels are ratios to the mean value for normal oesophagus. Values are mean (SD) of 6–8 experiments.