Dopamine D2 Receptor Is Involved in Alleviation of Type II Collagen-Induced Arthritis in Mice

Figure 2

D2-like receptor agonist quinpirole alleviates clinical symptoms and downregulates Th17-related cytokines and upregulates Treg-related cytokines in ankle joints in CIA mice. Mice were intraperitoneally administered with the D2-like receptor agonist quinpirole twice a week for three weeks dating from day 18 after primary immunization. The clinical arthritis score of four limbs was observed every other day beginning from day 21 until day 41 after immunization (a). The ankle joint width, hind paw thickness, and serum anti-CII IgG titer were measured on day 41 after immunization (b). Protein expression of the cytokines in ankle joints was examined on day 41 after immunization (c). Quin: quinpirole; versus intact; , versus CIA + vehicle.

(a)

(b)

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