Abstract
To test the hypothesis that the high absorption of manganese (Mn) in suckling rats compared to weanling rats is due in part to maturational differences in mucosal cell uptake of Mn, uptake kinetics of Mn were examined in isolated brush-border membrane vesicles prepared from the small intestine of rats at various ages (d 14, d 18, d 21). Initial uptake of Mn was rapid by vesicles from all age groups and reached an equilibrium plateau by 5 min in vesicles from suckling rats (d 14) and 10 min in vesicles from weanling rats (d 18, d 21). Uptake of Mn was associated with an osmotically active space. Uptake velocity was similar in all age groups and was nonsaturable at Mn concentration of 1-90 μM. The data were representative of a diffusional transport process. Mn uptake did not appear to be influenced by a putative ligand, L-histidine. However, incubations that included ascorbate did result in increased uptake of Mn by membrane vesicles. The results do not support the hypothesis that age-related differences in Mn retention in rats are due to maturational differences in the transport of Mn across small-intestinal brush-border membranes.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 387-398 |
| Number of pages | 12 |
| Journal | Journal of Toxicology and Environmental Health |
| Volume | 26 |
| Issue number | 4 |
| State | Published - 1989 |
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ASJC Scopus subject areas
- Pollution
- Toxicology
Cite this
Higher retention of manganese in suckling than in adult rats is not due to maturational differences in manganese uptake by rat small intestine. / Bell, J. G.; Keen, Carl L; Lonnerdal, B.
In: Journal of Toxicology and Environmental Health, Vol. 26, No. 4, 1989, p. 387-398.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Higher retention of manganese in suckling than in adult rats is not due to maturational differences in manganese uptake by rat small intestine
AU - Bell, J. G.
AU - Keen, Carl L
AU - Lonnerdal, B.
PY - 1989
Y1 - 1989
N2 - To test the hypothesis that the high absorption of manganese (Mn) in suckling rats compared to weanling rats is due in part to maturational differences in mucosal cell uptake of Mn, uptake kinetics of Mn were examined in isolated brush-border membrane vesicles prepared from the small intestine of rats at various ages (d 14, d 18, d 21). Initial uptake of Mn was rapid by vesicles from all age groups and reached an equilibrium plateau by 5 min in vesicles from suckling rats (d 14) and 10 min in vesicles from weanling rats (d 18, d 21). Uptake of Mn was associated with an osmotically active space. Uptake velocity was similar in all age groups and was nonsaturable at Mn concentration of 1-90 μM. The data were representative of a diffusional transport process. Mn uptake did not appear to be influenced by a putative ligand, L-histidine. However, incubations that included ascorbate did result in increased uptake of Mn by membrane vesicles. The results do not support the hypothesis that age-related differences in Mn retention in rats are due to maturational differences in the transport of Mn across small-intestinal brush-border membranes.
AB - To test the hypothesis that the high absorption of manganese (Mn) in suckling rats compared to weanling rats is due in part to maturational differences in mucosal cell uptake of Mn, uptake kinetics of Mn were examined in isolated brush-border membrane vesicles prepared from the small intestine of rats at various ages (d 14, d 18, d 21). Initial uptake of Mn was rapid by vesicles from all age groups and reached an equilibrium plateau by 5 min in vesicles from suckling rats (d 14) and 10 min in vesicles from weanling rats (d 18, d 21). Uptake of Mn was associated with an osmotically active space. Uptake velocity was similar in all age groups and was nonsaturable at Mn concentration of 1-90 μM. The data were representative of a diffusional transport process. Mn uptake did not appear to be influenced by a putative ligand, L-histidine. However, incubations that included ascorbate did result in increased uptake of Mn by membrane vesicles. The results do not support the hypothesis that age-related differences in Mn retention in rats are due to maturational differences in the transport of Mn across small-intestinal brush-border membranes.
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M3 - Article
C2 - 2709434
AN - SCOPUS:0024599449
VL - 26
SP - 387
EP - 398
JO - Journal of Toxicology and Environmental Health
JF - Journal of Toxicology and Environmental Health
SN - 0098-4108
IS - 4
ER -