Fig. 5. PKC acts upstream COX-2. (A) Effect of PGE2 (100nM; 2hours) on the ATPase activity when cells were pre-treated for 30 min with calphostin C (50 nM). (B) Effect of PMA (100nM, 2hrs) on the activity of the Na⁺/K⁺ ATPase, in presence of Indomethacin (100 µM) added 30min before). Values are means ± SEM of at least 3 observations. Bars not sharing a common letter are considered significantly different from each other at: p< 0.01.