Copper within Vertebrate Cells
Beginning with Thiers and Vallee (1957), a number of research group have examined the subcellular distribution of copper among organelles of liver cells, with fairly consistent results. Some of the data are presented in Table 6-1 and show that the largest portion of copper, in livers of normal adult rats or humans, is in the soluble (supernatant) fraction obtained by centrifuging for 60 min at 100,000 × g. This would represent copper binding to components of the cell cytosol, possibly excluding very large molecules that might have sedimented out. The next most abundant compartment is probably the nucleus, although, in these kinds of studies, unbroken cells will contaminate the nuclear fraction and add to its total copper content. The mitochondrial and microsomal fractions have lower, but significant, amounts of copper as well. Livers of rats and humans differ primarily by having different percentages of total tissue copper in the cytosolic fractions, about 65% in the rat and about 80% in the human. Pig liver may have a lower percentage in the cytosol (about 40%) and a larger percentage (35%) in the nuclear fraction (Owen et al., 1977).
KeywordsCytochrome Oxidase Nuclear Fraction Amine Oxidase Copper Deficiency Lysyl Oxidase
Unable to display preview. Download preview PDF.