Autocrine signaling is a form of signalling in which a cell secretes a chemical messenger (called the autocrine agent) that signals the same cell. Autocrine signalling is a form of signalling in which the target cell is the secretory cell itself. ...
An example of an autocrine agent is the cytokineinterleukin-1 in monocytes. When this is produced in response to external stimuli, it can bind to cell-surface receptors on the same cell that produced it. Cytokines are small protein molecules that are the core of communication between immune system cells, and even between these cells and cells belonging to other tissue types. ... Interleukin-1 (IL-1) is secreted by the macrophages, monocytes and dendritic cells. ... MONOCYTES: Plural of monocyte. ... In biochemistry, a receptor is a protein on the cell membrane or within the cytoplasm or cell nucleus that binds to a specific factor (a ligand), such as a neurotransmitter, hormone, or other substance, and initiates the cellular response to the ligand. ...
They move by circulation or diffusion to their target cells, which may be nearby cells (paracrine action) in the same tissue or cells of a distant organ of the body.
The function of hormones is to serve as a signal to the target cells; the action of hormones is determined by the pattern of secretion and the signal transduction of the receiving tissue.
Many of the responses to hormone signals can be described as serving to regulate metabolic activity of an organ or tissue.