Role of hepatic metallothionein during perinatal development in the rat.
The concentration of metallothionein (MT) in the liver of the perinatal rat is relatively high at term and 7 days after birth and then decreases to barely detectable levels by day 28. The developmental pattern MT-zinc parallels that of MT. When challenged with a single injection of cadmium chloride, the 26-day-old rat responds with a dose-related increase in hepatic MT which sequesters both cadmium and zinc. When the 5-day-old rat is similarly challenged, induction of MT occurs only at the highest dose tested (6 mg Cd/kg); however, due to the pre-existence of MT in these younger rats, cadmium administered at the lower doses still binds to the MT in a dose-related manner. Despite the induction of MT seen in both age groups following the 6.0 mg/kg dose, exposure to that level of the metal produced death in 30% of the younger animals but in only 4% of the older animals. When cadmium was administered to pregnant rats on day 19 of gestation, it was found to produce a dose-related induction of maternal hepatic MT over the following 48 hr. In contrast, maternal exposure to the metal led to a significant depression of fetal hepatic MT over the same time interval.
D000818:Animals; D001835:Body Weight; D002105:Cadmium Poisoning / Q000378:metabolism; D002850:Chromatography, Gel; D005260:Female; D008099:Liver / Q000254:growth & development* / Q000378:metabolism; D008297:Male; D008431:Maternal-Fetal Exchange; D008667:Metalloproteins / Q000502:physiology*; D008668:Metallothionein / Q000502:physiology*; D009929:Organ Size; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D015032:Zinc / Q000378:metabolism
D008667:Metalloproteins; D008668:Metallothionein; D015032:Zinc