- Legend: Fast Scan Cyclic Voltammetry, FSCV; gram, g; kilogram; High Performance Liquid Chromatography, HPLC; kg; milligram, mg; milliliter, ml; Mu-Opioid Receptor, MOR; Not Assessed, N/A; Sodium chloride, NaCl; Positron Emission Tomography, PET; Ultra Performance Liquid Chromatography, UPLC; volume, v; weight, w