Peroxisome proliferator-activated receptor-γ coactivator-1 (PGC-1) is highly expressed in brown adipose tissue (BAT) and plays an important role in adaptive thermogenesis. The aim of this study was to assess the acute effect of a β3-adrenergic agonist (Trecadrine) and leptin on the expression of PGC-1 and PPARγ2 mRNA in BAT. Trecadrine produced a marked increase (4.5-fold) in PGC-1 mRNA compared to controls (P<0.001) without changes in PPARγ2 mRNA, whereas leptin administration did not alter either PGC-1 or PPARγ2 expression. These results show that selective stimulation of the β3-adrenoceptor rapidly upregulates the expression of PGC-1 in brown adipocytes without a concomitant increase in PPARγ2. Moreover, our results show that PGC-1 and PPARγ2 expression in BAT seems not to be acutely regulated by leptin
