Figure 3.

PGT modulates EP₁ Ca²⁺ responses induced by autocrine/paracrine PGE₂ signaling. (A) PGE₂ concentrations in media of EP₁-HEK and PGT-EP₁-HEK cells treated with 10 μmol/L bradykinin in the absence or presence of 5 μmol/L T26A for 30 min at 37°C. Medium [PGE₂] was lower in cells expressing PGT, but not when PGT was inhibited with T26A. Values are mean ± SEM (n = 3 for each experiment). *P < 0.05. (B) Bradykinin-induced EP₁ signaling (Ca²⁺ responses) in WT-HEK, EP₁-HEK, and PGT-EP₁-HEK cells. EP₁-expressing cells had a Ca²⁺ response to bradykinin above that of wild-type cells. In cells that were also expressing PGT, the PGT inhibitor T26A doubled the degree of signaling via EP₁. Data are mean ± SEM (n ≥ 4 for each experiment), with >100 cells analyzed per experiment and per experimental condition. *P < 0.05, ***P < 0.001.