To evaluate the effects of CSREA on pain-associated gene expression, mRNA levels of sodium voltage-gated channel alpha subunit 9 (SCN9A), acid-sensing ion channel 1 alpha (ASIC1A), and tachykinin receptor 1 (TACR1) were measured in RA-differentiated SH-SY5Y cells. The gene discussed is SCN9A; the disease is rheumatoid arthritis.