Where does exocytosis occur?

Exocytosis occurs in several cells in the body including neurons and pancreatic cells. Different cells use this active transport mechanism for different reasons.

Synaptic vesicle exocytosis occurs in neurons of the nervous system. Communication in nerve cells is conducted by transmitting electrical or chemical signals from one neuron to another. These signals are known as neurotransmitters and they are transmitted between cells by the process of exocytosis.

Exocytosis occurs differently in the pancreas. The hormones insulin and glucagon, which are produced by small clusters of cells in the pancreas, are stored in secretory cells to be released on receiving specific signals. These hormones are released by exocytosis on receiving the relevant signal. Insulin is released when glucose levels in the blood are too high and glucagon is released when glucose levels are low.

The pancreas also uses exocytosis to secrete digestive enzymes such as amylases, proteases, and lipases.