Fig. 6. The effects of FGF21 on body weight and BAT thermogenesis are dependent on D2R in the LHA/ZI.
a–d, Effect of injecting adenoviral particles encoding GFP or shD2r (D2R-KD) into the LHA/ZI of rats fed a CD and treated with ICV FGF21 on cumulative food intake (a); infrared thermal images and quantification of BAT interscapular temperature (b); BAT protein levels of PGC1α and UCP1 (c); and quantification of immunolabelling for UCP1 in BAT (d). e, Photomicrographs showing the colocalization of GFP and c-Fos in the LHA/ZI of D2r-cre GFP mice treated with ICV FGF21, or shD2R + FGF21 ICV, demonstrating lack of c-Fos activation in LHA/ZI D2r neurons following D2r knockdown. f–j, Effect of injecting an adenoviral vector encoding a scrambled RNA (Ad-hSyn-DIO-EGFP) or an shRNA against D2r (Ad-hSyn-DIO-shD2r-EGFP) in a Cre-dependent manner followed by ICV injection of vehicle or FGF21 into D2r-Cre mice on body weight change (f); cumulative food intake (g); infrared thermal images and quantification of BAT interscapular temperature (h); quantification of immunolabelling for UCP1 in BAT (i); and BAT protein levels of PGC1α and UCP1 (j). Protein data were expressed as percentages in relation to control (GFP vehicle) animals. β-actin was used to normalize protein levels. Dividing lines indicate splicing within the same gel. Values are represented as means ± s.e.m., n per group. Exact P values are shown. Statistical differences were determined by a two-sided Student’s t-test (normal data; a, d and f–i) or a two-sided Mann–Whitney U test (non-normal data and non-homogeneous variance; b, c and j).