(A) In striatum, tonic and (B) phasic stimulation-induced DA release are both decreased significantly by 10 weeks of age (stim. intensity 10 V). (C) In NAc shell, the decline of tonic release was not significant until 12 weeks of age. (D) Phasic DA release also decreased more slowly in NAc than in striatum, with significant decline only at 12 weeks and later. Representative IT and CV traces of evoked DA signals in (E) striatal slices and (F) NAc shell slices at each stage in MitoPark and WT mice. Mean ± s.e.m. *P < 0.05, **P < 0.01, ***P < 0.001, compared to 8 weeks old wild type mice. For statistical details see Table 2.