Figure 5

The effect of parkin protein loss on the striatal levels of trace amine-associated receptor 1. (A) Tissue lysates were prepared from striata of the 2 month-old parkin knockout (PKO) and wild type (WT) Long Evans male rats. (a) Validation of antibody against trace amine-associated receptor 1 (TAAR-1). There was no signal for TAAR-1 receptor in striatal slices from TAAR1^−/− knockout rats. (b, c) Immunochemical staining of striatal slices from the WT rats and the PKO rats with the TAAR-1 antibody revealed diffuse cytoplasmic signal. (d) The no-primary antibody negative control for TAAR-1 antibody. (e) Quantification of TAAR-1 immunostaining revealed decreased levels of the receptor in the PKO rats compared to the WT controls (−33%, Student’s t-test, p < 0.01, n = 3). (B) Assessment of TAAR-1 levels in striatal lysates by SDS-PAGE and western blotting. The immunoreactivity of the 56 kDa band (glycosylated TAAR-1) was significantly decreased (−36%, p < 0.01, two-way ANOVA followed by Holm-Sidak’s post hoc test, n = 9) in the striatum of PKO rats compared to the WT controls. (C) The immunoreactivity of 56 kDa TAAR-1 band in the cerebellum of PKO rats did not show a decrease. The data are expresses as mean ± SEM, **p < 0.001.