Metallothionein production: similar responsiveness of avian liver and kidney to chronic cadmium administration.
The accumulation of hepatic and renal Cd, Zn, Cu, and metallothionein (MT) was investigated in ringed turtle doves (Streptopelia risoria) chronically exposed to 3 different concentrations of dietary Cd. When only tissue-Cd was considered as an inducer of MT, kidney was found to be 35% as responsive as liver in producing MT. However, when all potentially relevant inducing metals (Cd + Zn + Cu) were taken into account, kidney was found to be 85% as responsive as liver. The greater production of MT/mol Cd in liver was accounted for mainly by a greater co-accumulation of Zn/mol Cd in liver than in kidney. We conclude that the apparent tissue specificity in expression of MT may be overestimated by failure to consider fluctuations in multiple inducers. Variability in tissue-MT concentrations after chronic dietary Cd administration is best accounted for by a consideration of tissue-Cd, -Zn, and -Cu, rather than tissue-Cd alone.
Scheuhammer
A M
AM
Environment Canada, Canadian Wildlife Service, Ottawa, Ontario.
Templeton
D M
DM
D000818:Animals; D001717:Birds; D002104:Cadmium / Q000008:administration & dosage* / Q000378:metabolism / Q000633:toxicity; D003300:Copper / Q000378:metabolism; D004032:Diet; D007668:Kidney / Q000187:drug effects* / Q000378:metabolism; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008668:Metallothionein / Q000096:biosynthesis*; D012044:Regression Analysis; D015032:Zinc / Q000378:metabolism
D002104:Cadmium; D003300:Copper; D008668:Metallothionein; D015032:Zinc