MODERATE COPPER DEPRIVATION DURING GESTATION AND LACTATION AFFECTS DENTATE GYRUS AND HIPPOCAMPAL MATURATION IN IMMATURE MALE-RATS

The hippocampal formation (HF) is involved in higher brain functions i ncluding learning and declarative memory. The possibility that dietary copper has a role in the morphological development, and therefore the function of the HF, has received little attention. A rat model of tie red copper deficiency, initiated during gestation, was employed to det ermine the susceptibility of the HF, regions of which develop postnata lly, to copper deficiency. At postnatal 23, pups whose dams had receiv ed either 1.8 or 1.4 mg Cu/kg diet during both gestation and lactation , compared with offspring of a group that had received 4.3 mg Cu/kg di et during both periods had, significantly more cell nuclei in the infr apyrimidal arm of the dentate gyrus. Offspring of rats fed 1.4 mg Cu/k g diet, but not those fed 1.8 mg/kg, compared with those fed 4.3 mg/kg , exhibited smaller, shorter, and narrower cell nuclei in the infrapyr imidal and suprapyrimidal arms of the dentate gyrus and smaller cell n uclei in region CA3c of the hippocampus. A fourth group (gestation, 1. 8 mg Cu/kg diet; lactation, 0.9 mg Cu/kg diet) exhibited alterations l ess marked than those exhibited by the group fed 1.4 mg Cu/kg diet. Al l alterations in the groups fed low copper diets were consistent with slowed cell nuclear maturation, The Endings indicate that copper is re quired for maturation of the dentate gyrus and hippocampus. Also, copp er supplied at or below 1.8 mg/kg is insufficient for morphological ma turation of the dentate gyrus and hippocampus. Because the BE is impor tant for higher brain functions, further research is needed to determi ne whether the copper deficiency-induced alterations in dentate gyrus and hippocampus development are transient or permanent.