Cardiotoxicity in magnesium-deficient rats fed cadmium.
We studied the cardiotoxicity in magnesium (Mg)-deficient male rats fed 50 micrograms/g Cd for 45 consecutive days. Cd at a low concentration (0.28 ppm) in the heart induced cardiotoxic effects manifested by a decrease of the heart rate and weight and histopathological changes in the presence of Mg deficiency through Cd supplementation to a normal diet did not induce any cardiotoxic effect. Cardiac output (CO) did not increase in response to the decrease in the total peripheral resistance (TPR) in the Mg-deficient rats fed Cd, suggesting that supplementation of Cd to the Mg-deficient diet may lead to a decrease in the myocardial contractile function. However, supplementation of Cd to Mg-deficient diet also alleviated myocardial necrosis and Ca overload observed in the heart of Mg-deficient rats. The present data suggest that Cd ameliorates Ca overload in the heart of Mg-deficient rats but also may inhibit the release of Ca2+, which is a major determinant of the level of contractile force.
Nishiyama
S
S
Department of Environmental and Occupational Health, Kochi Medical School, Japan.
Saito
N
N
Konishi
Y
Y
Abe
Y
Y
Kusumi
K
K
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002104:Cadmium / Q000494:pharmacology*; D002302:Cardiac Output / Q000187:drug effects; D004032:Diet; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D008275:Magnesium Deficiency / Q000150:complications / Q000503:physiopathology*; D008297:Male; D008670:Metals / Q000097:blood / Q000378:metabolism / Q000652:urine; D009200:Myocardial Contraction; D009929:Organ Size; D051381:Rats; D011919:Rats, Inbred Strains
D008670:Metals; D002104:Cadmium