The Peripheral Benzodiazepine Receptor (PBR) is a protein located on the outer membrane of mitochondria, closely associated with cholesterol transport, cell proliferation, and death processes. It belongs to the transmembrane protein family, with multiple transmembrane domains. PBR is expressed in a variety of cells and tissues, especially in the adrenal gland and central nervous system. It is involved in multiple signaling pathways, particularly those related to mitochondrial function and cellular stress responses. The expression of PBR's gene is regulated by various factors, including hormone levels and inflammation status. Mutations or functional abnormalities in PBR are associated with the development of various diseases, including neurodegenerative diseases and cancer.