Other chemical mediators
There is wide variation in the structure and function of the different types of endogenous molecules which act as signal transmitters, from tiny gasses such as nitric oxide and carbon monoxide (sometimes referred to collectively as gasotransmitters), through neurotransmitters to peptide hormones and growth factors. In the Peptides section we provide information relating to the different families of peptide hormones, mediating a wide variety of signals responsible for controlling many essential biological processes. In this section we provide information related to important 'other' types of endogenous signaling molecules.
Some signaling molecules are small molecules which bind to cell surface receptors to modulate a signalling cascade and others are able to cross the cell membrane to exert their effects intracellularly. Signalling by these mediators can be by endocrine, paracrine or autocrine mechanisms.
Gasotransmitters, neurotransmitters, steroid hormones and eicosanoids are all examples of endogenous cell signaling molecules.