Figure 9.

Neutralization of IL-1 reduces cell loss induced by poly(I:C) and 6-OHDA. A, Experimental timeline: rats received a single intranigral injection of 20 μg of poly(I:C) and 9 d later started on either IL-1ra or vehicle, which continued through the experiment. All animals received an intrastriatal injection of 5.0 μg of 6-OHDA 12 d after vehicle/poly(I:C) injection and were allowed 21 d until postmortem analyses. B–E, Representative nigral and striatal sections stained for TH from rats treated with vehicle (B, D) or IL-1ra (C, E). F, Stereological quantification TH⁺ cells in the SNc revealed that IL-1ra prevented dopaminergic cell loss associated with poly(I:C) and 6-OHDA. G, Optical densitometric quantification of the TH-immunoreactive fibers in the striatum revealed that IL-1ra prevented TH fiber loss in the striatum. Data are shown as mean ± SEM. Vehicle, n = 11; IL-1ra, n = 12. **p < 0.01, unpaired t test. Scale bars: B, C, 0.25 mm; D, E, 1.0 mm. SNr, Substantia nigra pars reticulata.