(A) Schematic representation of pharmacological treatment administered and analyses. (B) Results from the rotarod test performed at 16, 24, and 32 rpm by mice between 5 and 15 weeks of age. Values represent the number of falls within 60 seconds as the mean ± SEM (WT n = 16; R6/2 n = 23; after surgery: WT n = 11; R6/2 LNA-SCB n = 11; R6/2 LNA-CTG n = 12). ***P < 0.001 versus WT vehicle-treated mice, as determined by 2-way ANOVA with Bonferroni’s post-hoc correction. (C) WT HTT (WT-HTT) and mutant HTT-e1 (mHTT) protein levels in the striatum of WT and R6/2 mice following intrastriatal injection of LNA-SCB or LNA-CTG, as analyzed by Western blotting. Box plots show the percentage of HTT and mHTT in the striatum of WT and/or R6/2 mice at different time points after LNA-ASO injection. Densitometric HTT and mHTT determinations were normalized using α-tubulin as an endogenous control and expressed as a percentage of a WT or R6/2 sample. Representative immunoblots are shown. WT: LNA-SCB–injected WT mice; sR6: LNA-SCB–injected R6/2 mice; aR6/2: LNA-CTG–injected R6/2 mice. Data were analyzed with Kruskal-Wallis (WT-HTT) and Mann-Whitney U (mHTT) tests (n = 4–12 animals per group). (D) HTT-e1 RNA transgene expression was analyzed by RT-PCR using the primer sets HTT_e1* or HTT_e1. Representative PCR products from animals injected with LNA-CTG or LNA-SCB are shown. β-Actin and Gdx amplification was used for internal controls. Box plots show RQ (obtained by densitometry) of HTT-e1 PCR products normalized to β-actin levels and referred to a control R6/2 LNA-SCB sample with a value of 1. *P < 0.01, when comparing LNA-SCB versus LNA-CTG–injected R6/2 mice in HTT_e1* PCR amplifications; Mann-Whitney U test with Bonferroni’s correction (n = 5–8 mice per group).