SLC18A2 and Parkinson disease: As expected from other animal studies and early PD cases13,37, we observed significantly decreased [11C]-DTBZ BPND to the VMAT2 in striatum, the major site of dopaminergic terminal density, and a similar trend in the ventral midbrain (site of dopaminergic cell bodies) and anterior pons (site of noradrenergic and serotonergic cell bodies) after repeated injections of lactacystin up to 200 μg.