↑ Severity of DSS-induced colitis in drd5-KO mice and in WT recipients following bone marrow transplant from drd5-KO mice↑ TNF-α, IL-6, NF-κB, and CCL2 in drd5-KO mice (blocked by dopamine)↓ CD86, ↓ iNOS and ↑ M2-polarization markers with dopamine. The gene discussed is CCL2; the disease is colitis.