Influence of Lead and Cadmium on the Susceptibility of Rats to Bacterial Challenge

Abstract

I.v. administration of an acute dose of lead acetate or cadmium acetate enhanced the susceptibility of rats to i.v. challenge with Escherichia coli by .apprx. 1000-fold. Since equivalent vulnerability of Pb- or Cd treated rats to killed E. coli was observed, toxicity is probably due to the endotoxin content of the bacteria. Equal doses of the gram-positive bacteria Staphylococcus epidermidis failed to elicit lethality in the acute Pb-intoxicated rats. The synthetic glucocorticoid methylprednisolone prevented lethality induced by the gram-negative bacteria in Pb-treated rats. It did not afford significant protection in Cd treated rats in the presence of E. coli. Marked alterations in hepatic morphology were apparent in Pb- and Cd-treated rats challenged with E. coli.