Fig. 5

Dose–response curves of PGE₂ stimulation with and without EP4 antagonist GW627368X (GW-X) and calculated mean EC₅₀ values. A: X-axis: PGE₂ concentrations scaled logarithmically. Y-axis: changes in SCC. Triangles (black) show increases in SCC as a response to PGE₂ doses without the addition of GW-X. Big dots (black) show increases in SCC in the presence of EP4 antagonist GW-X followed by PGE₂ stimulation. The small dotted and the unbroken line (blue colors) resemble single (srm) and two receptor model (trm) fitting. Long dotted line (red) shows srm for experiments with GW-X, trm could not be calculated. B: Mean EC₅₀ (nM) values of PGE₂ and EP4 agonist TCS 2510 following inhibition with GW627368X (GW-X), calculated from single receptor model (srm) equations. Numbers under the graph show N/n, N = number of patients, n = number of biopsies. Data are presented as means ± SEM