Cholinergic signaling in adipose tissue

Until recently, the role of direct cholinergic regulation of adipose tissue function was unclear. With the identification of the α2 nicotinic acetylcholine receptor as a key regulator of adaptive thermogenesis in white adipose tissue, there is evidence of direct cholinergic regulation of adipocyte physiology. As in the spleen and the bone marrow, there is a local source of nonneuronal acetylcholine in adipose tissue: Macrophages release acetylcholine in response to a multiplicity of stimuli including cold, norepinephrine, and fibroblast growth factor 21, integrating cholinergic signaling in the adipose tissue microenvironment. The recent insights on this cholinergic signaling provides a useful framework for further mapping of the physiology of cholinergic signaling in adipose tissue.