The analysis revealed that the levels of IL-1ra, IL-1β, IL-5, IL-12p70, IL-13, IL-15, MIP-1β, bFGF, and RANTES in the plasma of heroin addicts in the AW and PW stages were not significantly different from those in the plasma of the control group subjects (data not shown). Here, FGF2 is linked to heroin dependence.