Plasma Membrane Involvement in Brown Fat Thermogenesis

Abstract

Recent experiments indicate that plasma membranes of brown adipocytes contain distinct α- and β-adrenergic receptors able to recognize norepinephrine. Although activation of either receptor leads to brown fat thermogenesis via pathways that have some, but not all, events in common, the β-induced calorigenesis appears quantitatively greater than that elicited by the α-pathway. The sensitivity of the adrenergic-evoked respiration to Na⁺/K⁺ pump blockade as well as to atractyloside supports the view that a significant portion of brown fat thermogenesis reflects increased ATP turnover and enhanced mitochondrial ATP synthesis.

Supported in part by NASA Grant NGR-004-099 and Faculty Research Grant D816 from the University of California at Davis.