EFFECT OF STRESS ON THE RESPONSE OF RAT-BRAIN TO MANGANESE

Rats were immobilized for 2 hr and treated with MnCl2·4H2O, (4 mg Mn2+/kg) ip daily for 30 days to investigate the neurotoxic effects of manganese combined with immobilization stress. The increase in the brain concentration of the metal was almost identical after the treatment with manganese alone or in combination with immobilization of the rats. The results indicated that stress did not influence the central nervous system balance of manganese. Marked alterations in the contents of tyrosine, tryptophan, dopamine, and norepinephrine in the brain tissue of rats after the combined treatment with immobilization and manganese suggested that the neurotoxic effects of the metal may be more pronounced in a stressful situation. © 1979.