Chemische signalering in het endocriene systeem

A signaling cascade is a sequence of events that transfers information within or between cells, resulting in a response in the target cell.

Hormones are chemical messengers that trigger signaling cascades.

Lipid-soluble hormones, such as steroids or thyroid hormones, have intracellular receptors in the cytoplasm or nucleus of their target cells.

The binding of hormones to their intracellular receptors can lead to changes in cell metabolism and proliferation.                                                              

Testosterone is a steroid hormone that can quickly diffuse across the cell membrane into the extracellular fluid.

It attaches to transport proteins outside the cell to remain soluble in the bloodstream.

When reaching the target cell, testosterone detaches from the transport protein. It diffuses through the membrane and binds to an androgen receptor inside the cell.

This hormone-receptor complex can enter the nucleus and bind to a specific DNA sequence called a hormone response element. This binding regulates gene expression, triggering mRNA transcription and protein translation.