Selectivity of organ response to cadmium injury and various protective measures.

Abstract

This study was set up to investigate the lethality of cadmium and with the use of radioactive cadmium to determine whether cysteine causes any alterations in distribution of cadmium that might alter its toxicity. Comparisons were made with BAL selenium and zinc as well as with various other amino acids. After subcutaneous administration of cadmium chloride (.012 mM/kg) the testes of CD-1 mice undergo total destruction although only .1% of the dose administered (.07 mcg cadmium) reaches the gonads. In terms of concentration the testes is vulnerable to as little as .15 mcg of cadmium per gm wet weight of tissue; liver and kidney which attain concentration levels 45-90 times greater show no microscopic evidence of damage. Cysteine prevents cadmium from injuring the testes but enhances the lethality of cadmium 5-fold; greatly increased quantities of the metal are directed to the kidney selectively destroying the proximal convoluted tubules. BAL selenium and zinc which also protect the testes from cadmium neither increase the distribution of cadmium to the kidney nor enhance the toxicity of cadmium. Other than cysteine none of the 13 other amino acids tested protects the testes or increases cadmium toxicity. In contrast to the kidney the testis is protected in the face of the increase in cadmium level caused by both cysteine and selenium.