EN
Lead is known to be a potent neurotoxic agent. The interactions of lead with proteins are considered to be at least one of the mechanisms due to which lead exerts its toxicity. In the present work we demonstrate that acute and chronic models of exposure to lead affected the level of total and protein-bound SH groups in homogenates and synaptosomes obtainded from rat brains. The concentrations of SH groups were lowered significantly (P less then 0.05) in both types of poisoning. Different classes of cellural proteins were considered to play a role in high affinity binding of lead to these ligands.