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Abstract Zinc (zn) is indispensable to the human as and essential constituent of over 200enzymes and as an essential component for the structural integrity of cell membranes and some hormones. Intestinal absorption of zinc is facilitated by a zinc binding ligand thought to be of pancreatic origin. Zinc in plasma is transported primarily as a loosely bound complex with albumin (60-70 %) with lesser amourits bound to a-2 macroglobulin, transferrin, and amino acids. Serum zmc levels are depressed in hypoalbuminemic conditions as alcoholic cirrhosis, protein calorie malnutrition, and in old age due to physiologic hypoalbuminemia. Zinc levels in serum also decrease by 100/0 to 60% after several hours with any acute inflammation or infections or stressfull reactions and return to normal during convalescence. This reduction in serum zinc during inflammatory or infective conditions is not indicative of zinc defeciency and was attributed to redistribution of zinc to other body tissues, especially the liver which is believed to be mediated by a hormone like substance, termed leucocyte endogenous mediator (LEM). |