To evaluate whether cytokines are altered in peripheral blood of rats transgenic for the human Huntington´s disease mutation we investigated serum levels of GRO/KC, IL-1β, IL-13 and TNF-α at a symptomatic stage at 12 months of age. Overall serum levels of these cytokines were not significantly changed between transgenic HD rats and controls. Moreover, we observed a high interindividual variability. Our results indicate that these cytokines will be difficult to pursue as biomarkers in at least this rat model of HD.