What are some examples of paracrine signaling?

One common example of this type of signaling is synaptic signaling. In synaptic signaling, nerve cells transmit signals, and the junction between two nerve cells where signal transmission happens is known as the synapse. Once a neuron fires, an electrical impulse moves rapidly through the cell. When it reaches the synapse it generates the releases of neurotransmitters which rapidly move across the gap between nerve cells. Another example of paracrine signaling is nitric oxide functioning as a paracrine signaling molecule. Nitric oxide has a very short duration of action and diffuses towards smooth muscle cells to facilitate vasodilation. Another example is the ACh transmitted from a nerve to muscle which allows it to contract. Blood clotting is another example of paracrine signaling. Broken endothelial tissue releases signaling molecules such as thromboxane A2 into the affected tissue. These molecules act as paracrine signals and activate nearby platelets to bind to the site of injury.