Figure 3.

Suppression of arthritis in collagen-induced arthritis is ERα mediated. DBA/1J mice were immunized at day 0 and boosted at day 21. Arthritic animals (n = 12 per group) were daily, orally (p.o.) treated with vehicle (gelatin-mannitol), prednisolone (1.5 mg/kg or 3 mg/kg), (a) ethinyl estradiol (EE) at (0.025, 0.25 and 2.5 mg/kg) or the (c) estrogen receptor (ER)α agonist ERA-63 (0.75, 1.5 and 3 mg/kg). (a and c) The severity of arthritis was assessed by visual examination of a total of four paws/mouse (maximum is eight per mouse). The area under the curve (AUC) of the overall arthritis score is computed as a measure for the arthritis severity per animal during the 19 to 21 days of drug treatment for (b) EE and (d) ERA-63, respectively.