Time-course studies of pancreatic exocrine damage induced by excess dietary zinc in the chick.

Experiments were conducted to determine the time course of Zn-induced changes in the exocrine status of the chick pancreas. In experiments 1 and 2, chicks killed at intervals after the addition of excess Zn (500 mg/kg as ZnO) to a purified diet containing 70 mg Zn/kg showed a rapid increase in plasma Zn concentration that reached a plateau within 1 h. The pancreatic soluble Zn level increased linearly for 24 h, but then its rate of accumulation diminished.

Metalloforms of metallothionein induced by parenteral copper: the influence of route of administration.

Previous results regarding the two metalloforms of MT which accumulate in chick liver following the parenteral administration (ip) of copper were discussed. One metalloform, which is exclusively zinc, was suggested to reflect the marked accumulation of hepatic zinc following copper injection. The present report shows that there is a marked difference in hepatic zinc accumulation if copper is administered iv.

The toxicity of parenteral copper in the chick: dependence on route of administration.

Preliminary work in our laboratory suggested that the route of parenteral copper administration influences the acute toxicity of copper (Cu). The present work examined the effects of Cu given either intraperitoneally (i.p.

The ontogeny and induction by zinc of hepatic chick embryo metallothionein.

To avoid the maternal influences inherent in mammalian models, the chick embryo was examined for the effects of development on the ontogeny of hepatic metallothionein (MT) induction. Livers from embryos were examined for total and cytosolic zinc (Zn) and copper (Cu), and cytosolic MT on 12, 14, 16, and 18-21 days of incubation (DI) as well as 1, 7, and 14 days posthatch (ph). Cytosolic Zn levels fell, from a high on 12 DI (45.

Tissue-specific accumulation of metallothionein in chickens as influenced by the route of zinc administration.

The effect of the route of zinc (Zn) administration on the induction of metallothionein (MT) in various tissues of chicks was examined. Four-week-old, male chicks were assigned to one of four treatments: 5 mg Zn/kg intraperitoneal (i.p.