Endogenous metallothionein as determinant of intestinal cadmium absorption: A reevaluation

Foulkes, E. C.; McMullen, Diane M.

doi:10.1016/0300-483x(86)90144-7

Cited by 42 publications

(6 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The levels of 109 Cd in blood, liver and lung were higher at 2 h than at 24 h after dosing, probably re¯ecting a rapid absorption due to the high retention in the duodenum at 2 h. Starvation of the pups before gastric intubation leads to rapid stomach emptying and absorption. It has been proposed that Cd is tightly bound to metallothionein in the enterocytes, resulting in a delay or prevention of Cd uptake into the circulating blood (Foulkes and McMullen 1986;Min et al 1991;Squibb et al 1976). It might be that the basal rate of metallothionein production in the enterocytes of animals receiving an acute dose of Cd is too slow to delay or prevent the uptake.…”

Section: Fig 4a±ementioning

confidence: 98%

Bioavailability of cadmium from infant diets in newborn rats

Eklund

Grawé

Oskarsson

2001

Archives of Toxicology

View full text Add to dashboard Cite

Infants are exposed to higher levels of cadmium (Cd) from infant and follow-on formulas than from breast milk. We studied the bioavailability of 109CdCl2 from cows' milk formula, soy formula, wheat/oat/milk formula, wholemeal/milk formula and water in 11-day-old rat pups. The pups received a single oral dose of one diet labelled with 109Cd, 0.1 or 0.3 mg Cd/kg body weight. After 2 or 24 h or 4, 9 or 12 days the fractional retention of 109Cd in the whole body, in segments of rinsed small intestine and in tissue was measured in a gamma counter. Pups receiving 109Cd in water or cows' milk formula had the highest mean whole-body retention. It ranged from 67% of the dose in the water group to 52% in the wholemeal/milk formula group 4 days after dosing. The retention of 109Cd in the rinsed small intestine was significantly higher in the water group and the cows' milk formula group than in the cereal-based formula groups at 24 h and 4 days after dosing. It was still high in all groups on day 9, ranging from 26 to 11%. Initially most of the 109Cd was retained in the duodenum but by day 4 it had moved further down into the jejunum. In the liver, the highest and lowest retention on day 4 was 16%, and 3 per thousand of the dose in the water group and wholemeal/milk formula group, respectively. In the kidney, 109Cd was still increasing 12 days after exposure in all groups. Whole-body retention and tissue levels were higher than previously reported in adult animals. The lower bioavailability of 109Cd from the cereal-based formulas compared to water and cows milk formula on the longer survival times is most likely explained by Cd binding to dietary fibre and phytic acid in the cereal-based formulas reducing the intestinal binding and decreasing the bioavailability of Cd. The high retention of 109Cd in the small intestine, leading to a prolonged absorption period, emphasizes the importance of extending studies on neonatal Cd absorption over a long time period in order to detect for example, endpoints, accumulation of Cd in the kidney.

show abstract

Section: Fig 4a±ementioning

confidence: 98%

Bioavailability of cadmium from infant diets in newborn rats

Eklund

Grawé

Oskarsson

2001

Archives of Toxicology

View full text Add to dashboard Cite

show abstract

“…In mice, intravenous injection of 1 g Cd/kg is enough to induce it (Jonah and Bhattacharyya, 1989). Metallothionein has been reported to decrease gastrointestinal absorption of cadmium by decreasing the release of cadmium from the intestine and its transport to organs (Foulkes and McMullen, 1986;Sugawara and Sugawara, 1987;Ohta and Cherian, 1991).…”

Section: Toxicokinetics Of Cadmium In Ewesmentioning

confidence: 98%

Toxicokinetics of Cadmium in Lactating and Nonlactating Ewes after Oral and Intravenous Administration

Houpert

Federspiel

Milhaud

1997

Environmental Research

View full text Add to dashboard Cite

“…Just as different mechanisms may be responsible for transferring heavy metals across membranes in various cell types, it is not surprising to find that transcellular metal movement across an epithelial cell barrier, for example, may result from different processes at the apical and basolateral cell membranes. Suggestive evidence for such differences has been found for the rat jejunum (17). However, the observation that apical uptake of Cd is inhibited by Zn, whereas basolateral extrusion does not appear to be, could be related to the presumably very low concentration of free as opposed to total Zn in the cell.…”

Section: Some Basic Considerationsmentioning

confidence: 89%

Transport of Toxic Heavy Metals Across Cell Membranes

Foulkes

2000

Proc Soc Exp Biol Med

View full text Add to dashboard Cite

Abstract. Membrane transport of nonessential toxic heavy metals (type D heavy metals) not only controls their access to intracellular target sites but also helps determine their uptake, distribution, and excretion from the body. The critical role of membranes in the toxicology of class D metals has attracted the attention of many investigators, and extensive information has been collected on the mechanism(s) of metal transfer across membranes. Characteristics of metal transport in different cells, or even on opposite sides of the same cell, or under different physiological conditions, are not identical, and no unitary hypothesis has been formulated to explain this process in all cells. However, it seems possible that the mechanisms proposed for different cells represent variations on a few common themes.

show abstract

Endogenous metallothionein as determinant of intestinal cadmium absorption: A reevaluation

Cited by 42 publications

References 10 publications

Bioavailability of cadmium from infant diets in newborn rats

Bioavailability of cadmium from infant diets in newborn rats

Toxicokinetics of Cadmium in Lactating and Nonlactating Ewes after Oral and Intravenous Administration

Transport of Toxic Heavy Metals Across Cell Membranes

Contact Info

Product

Resources

About