The role of ACh in control of autonomic functions is well known, but it is likely that actions of ACh in the brain also modulate adaptive responses to environmental and metabolic conditions. Cholinergic signaling can alter thermoregulation (Myers and Waller, 1973), sleep patterns (Steriade, 2004), food intake (Grunberg et al., 1988; Mineur et al., 2011) and endocrine functions such as pancreatic release of insulin and glucagon (Ishikawa et al., 1982). The hypothalamus is essential for homeostatic responses regulating metabolism, and consequently, modulation of hypothalamic function by ACh is likely to be an important component of adaptation to peripheral autonomic signals to the brain.
