PGE₂ induces more robust cAMP generation in orbital compared to dermal fibroblasts resulting from higher levels of adenylate cyclase.

<p><b>A:</b> Confluent cultures were serum starved for 20 h and then treated with PGE₂ (1 µM) for 16 hrs. Cells were then lysed with 0.1 N HCl and cAMP was measured by cAMP immunoassay. Data are presented as the mean ± SD of three independent determinations. (* indicates statistical differences between groups). <b>B:</b> cAMP levels in three different dermal and orbital fibroblast strains treated with nothing or PGE₂ (1 µM) for 16 hrs. Data are presented as the mean ± SD of three independent determinations. The level of cAMP produced in orbital fibroblasts is 3 fold (p<0.05) greater than in dermal fibroblasts, <b>C:</b> Orbital fibroblasts express higher adenylate cyclase levels when compared to dermal fibroblasts. Data derived from Western blot analysis of three separate dermal and orbital fibroblast strains. These were normalized to their respective β-actin levels. They are expressed as the mean ± SD, p<0.005, n = 3.