A kinetic study of some factors which influence the intestinal absorption of calcium in rats.
Braz J Med Biol Res
; 24(2): 215-7, 1991.
Article
em En
| MEDLINE
| ID: mdl-1823234
Rats weighing 100 +/- 8 g were used in an in vivo kinetic study of the intestinal absorption of calcium (CaA) from three systems: 1) CaCl2, 2) whole cow's milk (M), and 3) a staple Brazilian diet (SBD). Food substrates were treated with HCl, neutralized and diluted with 0.15 mM NaCl to different concentrations. Each dilution was assayed by introducing 2 ml into the small intestine and the final amount of Ca2+ in the small intestine was determined 30 min later. The values for velocity (v = Vmax (Ca2+)/(Ca2+) + Km) and affinity (1/Km) for the food substrates were 1.35, 15.51 and 2.31 micrograms Ca2+/min and 0.29, 0.016 and 0.266 micrograms Ca2+/ml, respectively. We conclude that the higher affinities observed for CaCl2 and SBD were not correlated with velocity. Factors modifying CaA appear to be protein (stimulator) and phytate and fiber (inhibitors).
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cálcio
/
Absorção Intestinal
/
Intestino Delgado
Limite:
Animals
Idioma:
En
Revista:
Braz J Med Biol Res
Ano de publicação:
1991
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Brasil