Original records in individual rats of iBAT and core temperature (unbroken and broken lines respectively in top panels of A and B), and tail artery blood flow (bottom panels of A and B). At the time indicated by the double arrows environmental temperature was reduced from room temperature to 10°C. Either vehicle followed by vehicle (A, ie a Group A animal) or vehicle followed by MDMA (10 mg/kg, s.c.) (B, ie a Group B animal) was administered at the times indicated by single arrows. Cold exposure induced iBAT thermogenesis and reductions in tail blood flow that were unaffected by treatment with vehicle (A). MDMA transiently increased tail artery blood flow, and caused long-lasting reductions iBAT thermogenesis and core body temperature (B). In other experimental conditions (Groups C to E) WAY 100635, spiperone, or a combination of both drugs was injected at the time points indicated by the first and second single arrows. In these groups, MDMA was also injected at the time indicated by the second single arrow.