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 Ca (1.2%) or low Ca (0.005%) diets for 4 wk and exposed to Pb via drinking water containing lead acetate (0.032, 0.32 and 3.2 mg Pb/ml) for the last 3 wk of a 4 wk diet period. Control Pb-free groups of both dietary regimens received equimolar acetate as sodium acetate. The 8 groups (6 rats/group) were divided equally between the 2 diet regimens. Three week treatment with Pb 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 Ca alone reduced DA and NE in HME. In contrast with the HME low Ca diet alone had no significant effect on DA and NE in STR. No additive effect of low Ca diet and Pb ingestion in catecholamine reduction was found.