Purification, reconstitution, and functional characterization of zinc transporter from rat renal brush border membranes.

Abstract

Zinc is an integral component of a wide variety of functional proteins, enzymes, and transcription factors where it exerts specific actions over a wide range of physiological processes such as growth, development, and functioning of the endocrine, immune, and nervous systems (, , , ). Zinc is also involved in stabilizing membrane structure, and in protection at the cellular level by preventing lipid peroxidation and reducing free radical formation (). The primary site of zinc regulation in mammals is intestinal absorption. After being absorbed, zinc is bound to albumin in the circulation, where it is maintained within a narrow range (1 μg/mL) in mammals. Most of the zinc is taken up by the liver before being redistributed to other organs. The primary routes of zinc excretion are via pancreatic, biliary, and intestinal secretions. A very small amount of zinc is excreted by the kidney, as most of the zinc from the glomerular filtrate gets reabsorbed in the renal tubular system.