2.3. Microglial depletion

To deplete microglia during METH IVSA, CSF1R inhibitor PLX5622 (HY-114153, MedChemExpress, NJ, USA) was formulated in AIN-76A chow (1200 ppm; Research Diets, New Brunswick, NJ, USA). PLX5622 is highly selective to microglia has been shown to ablate nearly all microglia (>97 %) when administered for at least 5 days (Savage et al., 2019) (Supplementary Fig. 1). To determine the effect of microglia depletion on methamphetamine-taking, mice were treated with PLX5622 5 days prior to starting METH IVSA, and for the duration of Acquisition and Maintenance. To determine the effect of microglia depletion on methamphetamine-seeking, mice were treated with PLX5622 beginning after the last maintenance session and for the duration of forced home cage abstinence.