OBJECTIVE: To determine whether the dramatic reduction in expression and functional activity of the β 3-adrenergic receptor (AR) and β 1 AR subtypes originally observed in adipose tissue of the C57BL/6J Lep ob/Lep ob (‘obese’) mouse are general features of all models of obesity, and whether obesity-related differences in βAR subtype expression occur between adipose depots.

DESIGN: Survey of adipose tissue βAR expression from four mouse models of congenital obesity: the ‘obese’mouse (C57BL/6J Lep ob/Lep ob), the ‘diabetic’mouse (C57BL/KsJ LepR db/LepR db), the ‘tubby’mouse (C57BL/6J tub/tub) and the ‘fat’mouse (C57BL/KsJ Cpe fat/Cpe fat), and in a model of high-fat diet-induced obesity in C57BL/6J mice.

MEASUREMENTS: Expression of the βAR subtypes was measured by Northern blot hybridization in white and brown adipose depots.

RESULTS: In the severely obese Lep ob and LepR db mice, mRNA concentrations of β 3 AR and β 1 AR in white adipose tissue (WAT) were decreased by> 99% and by> 70%, respectively. More modest effects on β 3 AR expression were observed in brown adipose tissue (BAT, decreased by 20–30%). In less severe forms of obesity, as found in the tubby and carboxypeptidase (Cpe) fat mice, and in diet-induced obese B6 mice, β 3 AR expression was decreased in WAT by up to 90%, with more modest decreases in interscapular BAT (IBAT). Changes in β 1 AR mRNA concentrations were more variable. β 2 AR mRNA levels did not differ in most cases, with the exception that there was a 3–5-fold increase in BAT for both Lep ob and LepR db mice.