Recent evidence has linked inhibition of hypothalamic AMPK to activation of BAT thermogenesis (7,8). To further characterize the mechanisms mediating nicotine-induced negative energy balance, we examined the effects of nicotine on BAT temperature. Our data showed that nicotine-treated rats displayed a marked and significant increase in skin temperature surrounding interscapular BAT (Fig. 2F). In keeping with this effect, nicotine treatment for 48 h increased the expression of thermogenic markers such as UCP1 and peroxisome proliferator–activated receptor γ coactivator 1α and -β in BAT (Fig. 2G).
