The absorption of iron, calcium, phosphorus, magnesium, copper and zinc in the jejunum–ileum of control and iron-deficient rats

Abstract

The effects of iron deficiency on the absorption of different dietary sources of iron were studied, together with the interactions between iron, calcium, phosphorus, magnesium, copper and zinc in the jejunum-ileum of control and iron-deficient rats. In this study, three perfusion solutions containing different iron sources: ferric citrate, haemoglobin, and equal parts of ferric citrate and haemoglobin were used. In addition, the same perfusion solutions were used with and without 2,4-dinitrophenol, an inhibitor of oxidative phosphorylation. Iron absorption in anaemic rats was greater than in the controls, except after perfusion with solutions containing haemoglobin. The absorption of calcium, copper and zinc in iron-deficient animals was not significantly affected, while the absorption of phosphorus and magnesium increased, with respect to animals in the control group. After perfusion with solutions containing haemoglobin, the absorption values of calcium, copper and zinc were lower than after ferric citrate in both groups (control and iron-deficient rats).

Manganese deficiency and toxicity: Are high or low dietary amounts of manganese cause for concern?

“…Such factors include the type of dietary fat (saturated fats have been shown to promote Fe absorption as compared to unsaturated fats [34]) and the mucosal block of Fe absorption (preliminary data from this laboratory shows that mice mutant in a major histocompatability complex (MHC) receptor protein accumulate increased amounts of Fe and Mn in the liver). Magnesium deficiency has been reported to increase Fe accumulation in tissues [35] and Mg status affects Fe absorption [36][37][38]. In a recent study with Mg deficient swine, we observed a very high rate of seizures followed by sudden death in animals fed 50 mg Mn/kg diet, but not in animals fed 10 mg Mn/kg diet (unreported data).…”

Influence of the Extent of Haemoglobin Hydrolysis on the Digestive Absorption of Haem Iron in the Rat. an in Vitro Study

“…Therefore increasing haem uptake by the intestinal epithelium could be of interest in promoting haem iron bioavailability. Further studies are needed to assess the potential effect of peptides on the weak iron absorption that occurs in lower segments of the digestive tract (Gomez-Ayala et al 1997;: Ebihara et al 1994Campos et al 1996), which could be enhanced by an increased iron solubility.…”

Effect of calcium-supplemented goat or cow milk on zinc status in rats with nutritional ferropenic anaemia

“…The higher digestive and metabolic utilization of Zn (P < 0.001) in the anaemic rats than in the controls, regardless of the type of diet consumed, especially in normal Ca content diets (Table 3), may, according to Campos et al (1998) and to King and Keen (1999), be due to the deficiency of Fe in the intestinal region that produces an increase in the absorption of other divalent cations. However, Gó mez-Ayala et al (1998) demonstrated that in a situation of Fe deficiency, a greater absorption of Cu occurs, while that of Zn remains unchanged.…”