Signaling of nicotinic acetylcholine receptors in mononuclear phagocytes

Nicotinic acetylcholine receptors are not only expressed by the nervous system and at the neuro-muscular junction but also by mononuclear phagocytes, which belong to the innate immune system. Mononuclear phagocyte is an umbrella term for monocytes, macrophages, and dendritic cells. These cells play pivotal roles in host defense against infection but also in numerous often debilitating diseases that are characterized by exuberant inflammation. Nicotinic acetylcholine receptors of the neuronal type dominate in these cells, and their stimulation is mainly associated with anti-inflammatory effects. Although the cholinergic modulation of mononuclear phagocytes is of eminent clinical relevance for the prevention and treatment of inflammatory diseases and neuropathic pain, we are only beginning to understand the underlying mechanisms on the molecular level. The purpose of this review is to report and critically discuss the current knowledge on signal transduction mechanisms elicited by nicotinic acetylcholine receptors in mononuclear phagocytes.

Automated summary

Nicotinic acetylcholine receptors are expressed in not only the nervous system and neuro-muscular junction, but also in mononuclear phagocytes of the innate immune system. These cells, which include monocytes, macrophages, and dendritic cells, play important roles in host defense and inflammatory diseases. The stimulation of nicotinic acetylcholine receptors in these cells is associated with anti-inflammatory effects. However, the underlying molecular mechanisms are still not fully understood.