Figure 1.

Acute effects of glucagon are not solely mediated by brown adipose tissue (BAT). (A) Acute administration of glucagon increases energy expenditure in animal species with little or no functional BAT, like dogs and pigs, and in genetically modified mice lacking functional Ucp1 gene (Ucp1 KO) or glucagon receptor in brown adipose tissue (BAT^Gcgr−/−). (B) Both cold exposure and glucagon administration increased energy expenditure to a similar extent, while only cold exposure increased BAT activity.