Effects of copper administration on fetal and neonatal mice.

The effects of copper administration to neonatal male mice on the copper concentrations and activities of copper-containing enzymes in cerebrum, liver, and kidney were studied. Intraperitoneal copper injections at 7 and 10 days of age increased the activities of superoxide dismutase and cytochrome oxidase in cerebrum and liver, and also increased the copper concentrations in cerebrum, liver, and kidney at 13 days of age. Maternal copper administration during the late-gestational period (from 13 days gestation to delivery) decreased the activities of both enzymes and increased the copper concentration in cerebrum. This increased level of copper remained by 13 days of age after birth. Liver showed similar changes to those in cerebrum, but the renal responses were less remarkable. Maternal copper administration from the late-gestational through lactational periods affected neonatal growth, decreased the activity of cytochrome oxidase, and increased the copper concentrations in all tissues examined. It is known that the copper concentration and copper-containing enzyme activity are low in cerebrum of mottled mice as well as of patients with Menkes' disease. These results suggested that the cytochrome oxidase activity in cerebrum was decreased by not only copper deficiency but also excess. The combination of prenatal copper supplementation by means of maternal copper administration during the late-gestational period and intraperitoneal copper injections after birth, while being careful not to overdose, is expected to be efficient for the copper supplementation to mottled mice.