αSyn119 Expression in Catecholaminergic Neurons Leads to a Reduction of Striatal Dopamine and its Metabolites. Analysis of striatal biogenic amines in ROSA26-αSyn119 mice by HPLC with electrochemical detection. The level of dopamine (A, C), or the dopamine metabolites, DOPAC and HVA, and 5-HT (B, D) were measured by HPLC in striatal tissue from (A, B) 12–13 month-old female ROSA26-αSyn119+/-/nestin-Cre mice (Cre +) and their ROSA26-αSyn119+/- littermate controls (Cre -) and from (C, D) 10–11 month-old female ROSA26-αSyn119+/+/TH-Cre mice (Cre +) and their ROSA26-αSyn119+/+ littermate controls (Cre -). The concentration of each biogenic amine is expressed as ng per mg of protein, and data represent the mean ± SEM (n = 7–9 mice for nestin-Cre and n = 5–6 mice for TH-Cre). Significant differences between Cre- and Cre + genotypes were determined following statistical analysis by unpaired, two-tailed Student's t test (*p < 0.05, **p < 0.01).