The metabolic profile of compound [ 18 F]12 was assessed in plasma, brain and liver samples 60 min p.i. The radio-HPLC analysis of WT plasma samples revealed that the parental fraction was reduced to about 11% intact tracer 60 min p.i. (Figure ). Two new metabolites, [ 18 F]M1 (3%) and [ 18 F]M2 (86%), were formed. Liver samples contained equal ratios of intact tracer which also applies to PLX and Trem2 -/-mice (Figure ).