Regional alterations of brain catecholamines by lead ingestion in adult rats. Influence of dietary calcium.

The alterations in steady-state dopamine (DA) and norepinephrine (NE) content of hypothalamus-median eminence (HME) and striatum (STR) were measured in adult female rats fed normal calcium (1.2%) or low calcium (0.005%) diets for 4 weeks and exposed to lead via drinking water containing lead acetate (0.032, 0.32, and 3.2 mg Pb/ml) for the last 3 weeks of a 4-week diet period. Control lead-free groups of both dietary regimens received equimolar acetate as sodium acetate. The eight groups (six rats/group) were divided equally between the two diet regimens. Three weeks treatment with lead significantly reduced DA and NE in HME but DA only in STR (0.32 and 3.2 mg Pb/ml) of both dietary groups. Low dietary calcium alone reduced DA and NE in HME. In contrast with the HME low calcium diet alone had no significant effect on DA and NE in STR. No additive effect of low calcium diet and lead ingestion in catecholamine reduction was found in the brain parts studied.