UCP1 is essential for adaptive adrenergic nonshivering thermogenesis.
Participation of brown adipose tissue [through the action of the uncoupling protein-1 (UCP1)] in adaptive adrenergic nonshivering thermogenesis is recognized, but the existence of a response to adrenergic stimulation in UCP1-ablated mice implies that a mechanism for an alternative adaptive adrenergic thermogenesis may exist. Here, we have used UCP1-ablated mice to examine the existence of an alternative adaptive adrenergic nonshivering thermogenesis, examined as the oxygen consumption response to systemically injected norepinephrine into anesthetized or conscious mice acclimated to different temperatures. We confirm that UCP1-dependent adrenergic nonshivering thermogenesis is adaptive, but we demonstrate that the adrenergic UCP1-independent thermogenesis is not recruitable by cold acclimation. Thus, at least in the mouse, no other proteins or enzymatic pathways exist that can participate in or with time take over the UCP1 mediation of adaptive adrenergic nonshivering thermogenesis, even in the total absence of UCP1. UCP1 is thus the only protein capable of mediating cold acclimation-recruited adaptive adrenergic nonshivering thermogenesis.
Golozoubova
Valeria
V
The Wenner-Gren Institute, The Arrhenius Laboratories F3, Stockholm University, SE-106 91, Stockholm, Sweden.
Cannon
Barbara
B
Nedergaard
Jan
J
D000064:Acclimatization / Q000187:drug effects / Q000502:physiology; D000222:Adaptation, Physiological / Q000187:drug effects / Q000502:physiology; D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage*; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism*; D003080:Cold Temperature; D007473:Ion Channels; D008565:Membrane Proteins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL / Q000378:metabolism*; D024101:Mitochondrial Proteins; D009638:Norepinephrine / Q000008:administration & dosage*; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology*; D012768:Shivering / Q000187:drug effects / Q000502:physiology; D022722:Thermogenesis / Q000187:drug effects / Q000502:physiology*; D000071256:Uncoupling Protein 1
D000316:Adrenergic alpha-Agonists; D002352:Carrier Proteins; D007473:Ion Channels; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; C000604372:Ucp1 protein, mouse; D000071256:Uncoupling Protein 1; D009638:Norepinephrine