Biomaterial Database

Dietary regulation of copper absorption and storage in rats: effects of sodium, zinc and histidine-zinc. 1993

R A Wapnir, and S Y Lee

Department of Pediatrics, North Shore University Hospital-Cornell University Medical College, Manhasset, New York 11030.

Zinc (Zn) and L-histidine (His) are known competitors of intestinal copper (Cu) uptake. Sodium (Na) appears to be an enhancer of the luminal phase of Cu absorption. We investigated whether dietary treatment with these modifiers would alter Cu absorption and tissue stores of Zn and Cu in rats. Juvenile male rats were fed semipurified diets with adequate amounts of Cu, Zn and Na (Ctl), or with the addition of either excess Na (Hi Na), Zn (Hi Zn), or Zn plus His (Hi Zn+His) for 3 weeks. The jejunum was perfused in situ with 0.1 mM Cu, 1 mM His to determine Cu and water absorption rates. The lowest Cu absorption rate was observed in the Hi Zn+His group, and both the Hi Zn and Hi Zn+His had greater Cu accumulation in the small intestine than did Ctl or Hi Na rats. Hi Na had no effect on Cu transport. There was excess Cu accumulation in the kidneys of Hi Zn+His rats, and hepatic and kidney metallothioneins were also elevated. These results indicate that while a high Na intake does not affect Cu absorption, excess dietary Zn and His have greater effect than does Zn only in the limitation of Cu uptake.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D003300	Copper	A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.	Copper-63,Copper 63
D004032	Diet	Regular course of eating and drinking adopted by a person or animal.	Diets
D006639	Histidine	An essential amino acid that is required for the production of HISTAMINE.	Histidine, L-isomer,L-Histidine,Histidine, L isomer,L-isomer Histidine
D000042	Absorption	The physical or physiological processes by which substances, tissue, cells, etc. take up or take in other substances or energy.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23
D014018	Tissue Distribution	Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.	Distribution, Tissue,Distributions, Tissue,Tissue Distributions
D015032	Zinc	A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.
D017208	Rats, Wistar	A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.	Wistar Rat,Rat, Wistar,Wistar Rats