Among the various efflux transporters, P-glycoprotein (P-gp), multidrug resistance-associated proteins (MRPs), and the breast cancer resistance protein (BCRP) are the most extensively studied in the context of toxicology. These transporters are expressed in key tissues such as the liver, kidney, intestine, and the blood-brain barrier, where they regulate the absorption, distribution, and elimination of toxicants.
