Sustained Release of Prostaglandin E₂ in Fibroblasts Expressing Ectopically Cyclooxygenase 2 Impairs P2Y-Dependent Ca²⁺-Mobilization

Figure 1

PGE₂ released in MEFs overexpressing COX-2 and effect on P2Y-dependent Ca²⁺-mobilization. WT and KI (COX-2-deficient MEFs overexpressing COX-2) MEFs, treated in the absence or presence of LPS (200 ng/mL) plus cytokines (IFN-γ, TNF-, and IL-1, 20 ng/mL), were used. The protein levels of COX-1 and COX-2 and the PGE₂ released into the culture medium were determined by immunoblot and ELISA, respectively (a). The percentage of cells showing Ca²⁺-mobilization in response to the P2Y agonist UTP (100 μM) was determined using the nonratiometric Fluo-4 assay (b). Results show a representative blot (a) and the mean + SD of three experiments for release of PGE₂ to the culture medium and Ca²⁺-mobilization. , versus the corresponding control.

(a)

(b)