Comparative Ability of Exogenously Administered Metals to Alter Tissue Levels and Urinary Output of Copper and Zinc

Abstract

Various metal ions were administered to male Sprague-Dawley rats and their effects on copper and zinc metabolism examined. Of the metals tested, cobalt was unique in producing a substantial (200%) increase in urinary excretion of copper, which lasted through 72 h after a single dose (250 μmol/kg body weight); during the same time period zinc output in urine was markedly (40–50%) reduced. Decreased (≈30–40%) renal copper levels were observed following treatment with cobalt, tin, manganese, nickel and iron. Such changes indicate the existence of important biological interactions of exogenously administered metals with endogenous trace elements, and suggest the possibility of utilizing metals such as cobalt to modulate experimentally copper and zinc metabolism.

Essential Elements as Early Indicators of Hexavalent Chromium Nephrotoxicity

“…This phenomenon can be partly explained by the increase of metallothionein containing copper in the kidney and zinc in the liver as well as by the process of urinary excretion of this protein (Lee et al, 1983). However, it should also be noted that numerous metals, such as nickel, tin, lead, and cobalt, do not induce metallothionein but still cause renal damage accompanied by increased copper and zinc excretion in the urine (Chmielnicka et al, , 1982Chmielnicka, 1991;Rassenberg and Kappas, 1989). It was also noted that the levels of metallothionein in gentamicin-exposed rats were not changed, but elevated copper and zinc levels in urine that were parallel to histopatologic changes in kidneys were observed (Chmielnicka et al, 1992).…”

The Comparative Abilities of Inorganic Cobalt and Cobalt-Protoporphyrin to Affect Copper Metabolism and Elevate Plasma Ceruloplasmin

“…During recent studies on the acute effects of exogenous metals on trace element homeo stasis, we observed that cobalt was unique among the metals tested in its ability to accel erate urinary copper output in rats [9]. Inor ganic cobalt was found to elevate hepatic zinc levels while lowering renal copper concentra tions [10], In the present studies, we have compared the effects of inorganic cobalt with those of cobalt-protoporphyrin on copper and zinc metabolism in normal male SpragueDawley rats.…”

“…Copper and zinc levels were measured in tissue digests and column eluates in an air-acetylene flame using a 10-cm burner head and a flow spoiler at wavelengths of 324.8 and 213.9 nm, respectively. The graphite furnace utilized the L'vov platform [12] with appropriate wavelength and instrumental operating conditions as optimized in our laboratory for individu al metal analyses [9,10]. Recovery experiments were routinely carried out in each tissue to characterize the behavior of the particular metal within the given ma trix.…”

“…The column was eluted at a flow rate of 15 ml/ h with a fraction size of 5 ml. Fractions were moni tored for protein at 280 nm, and analyzed for zinc and copper concentration by fiameatomic absorption spec troscopy as described earlier [9,10].…”

Characterization of cobalt-copper antagonism in the study of copper-stimulated growth in weanling pigs

“…The unique ability of Co to increase Cu excretion was observed when Rosenberg and Kappas (1989a) were studying the interaction between Co and a number of metals including Cu. A subcutaneous injection of Co induced a rapid urinary excretion of Cu in rats (within 24 h).…”