Effect of ethanol on the distribution of cadmium between the cadmium metallothionein- and non-metallothionein-bound cadmium pools in cadmium-exposed rats.
In an attempt to assess the effect of ethanol on cadmium accumulation, metallothionein (MT) synthesis, Cd-binding capacity and lipid peroxidation, rats were administered either Cd, ethanol or their combination for a period of 4 weeks. A significant increase in Cd accumulation was observed in all the organs of rats under study co-exposed to Cd and ethanol as compared to only Cd-treated rats. Increased MT levels in response to Cd were associated with a marked alteration in the distribution of Cd amongst the two pools of intracellular Cd i.e. Cd bound to MT (Cd-MT) and Cd not bound to MT (non-MT-Cd). Higher levels of non-MT-Cd were observed in liver, kidney and heart of Cd+ethanol-exposed rats as compared to only Cd-exposed rats. Lesser binding of 109Cd to the protein peak was observed in Cd+ethanol-exposed rats than the Cd-treated rats when hepatic supernatants from all the groups were chromatographed on Sephadex G-75 columns, suggesting that ethanol has a redistributing effect on Cd amongst the two pools. A marked increase in lipid peroxidation was observed which was linear to the increase in non-MT-Cd levels. A positive correlation between non-MT-Cd levels and lipid peroxidation was observed in liver, kidney and heart suggesting that non-MT-Cd levels are more crucial and toxicologically more important than total Cd levels.
Sharma
G
G
Department of Biochemistry, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Nath
R
R
Gill
K D
KD
D000818:Animals; D002104:Cadmium / Q000378:metabolism* / Q000633:toxicity; D002850:Chromatography, Gel; D004347:Drug Interactions; D000431:Ethanol / Q000633:toxicity*; D007413:Intestinal Mucosa / Q000378:metabolism; D015227:Lipid Peroxidation; D008168:Lung / Q000378:metabolism; D008297:Male; D008668:Metallothionein / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013056:Spectrophotometry, Ultraviolet; D013154:Spleen / Q000378:metabolism
D002104:Cadmium; D000431:Ethanol; D008668:Metallothionein