Insulin is a hormone with a central role in the control of blood glucose, and as a logical consequence in the pathogenesis of diabetes. In this section we will answer some questions on this topic.

Where does insulin come from?

Insulin is secreted from a gland (pancreas) into the bloodstream.

How does insulin act?

Insulin circulates in blood and  reaches the cells of the body. We know that insulin connects with some structures located on the cell surface known as insulin receptors. This initial step starts a series of reactions inside the cell that leads to the activation of some molecules known as “glucose transporters  that allow the entrance of glucose into the cells.
This series of reactions is schematically represented in the following figure that can be downloaded in .ppt format and read with Power Point XP. The animations will clarify better the sequence of events