Regulation of brown adipose tissue thermogenesis by corticosterone in obese fa/fa rats.

The defective BAT function of obese Zucker rats has been related primarily to a loss of diet-induced thermogenesis. The normalisation of BAT function by adrenalectomy has been related to the removal of corticosterone. Experiments with propranolol-blockade and on tissue norepinephrine turnover suggest that corticosterone impairs diet-related sympathetic activity but does not alter BAT response to exogenous norepinephrine. The reduction in serum T3 in obese rats is related to the loss of sympathetic activity.