permeability glycoprotein (P-gp)

Permeability glycoprotein (P-gp) is a protein found in cell membranes that acts as a natural defense mechanism by pumping certain substances out of cells. Its primary role is to protect tissues by removing potentially harmful compounds, including some drugs, from entering cells or exiting them. P-gp is especially significant in organs like the intestines, liver, and brain, where it influences how drugs are absorbed, distributed, and eliminated. This function can affect the effectiveness of medications, as high P-gp activity may reduce drug accumulation in target tissues, impacting therapeutic outcomes.