Effect of subacute manganese feeding on serotonin metabolism in the rat.

To clarify the effect of subacute manganese feeding on serotonin and mineral metabolism, Wistar rats were separated into two groups and fed two different diets, on a normal diet and another a manganese-supplemented diet. After 3 wk on these dietary regimens, the rats on the manganese-supplemented diet manifested the following abnormalities: blood pressure was decreased, brain serotonin was decreased, aromatic L-amino-acid decarboxylase activity in the brain was decreased, and manganese levels in heart, lung, and kidney were increased, whereas sodium, potassium, magnesium, and calcium levels in the brainstem were decreased.