title: Zinc uptake by basolateral membrane vesicles from rat small intestine.
abstract: Zinc uptake (transport and binding) by basolateral membrane vesicles was investigated using membranes derived from small intestines of rats fed zinc-adequate and zinc-deficient diets. Uptake was separated into saturable and nonsaturable (diffusion) components. Kinetic analysis of initial rates of the saturable component of uptake (at 1 min) indicates half maximal uptake (Km) by vesicles from zinc-adequate rats was observed at a medium Zn2+ concentration of 24 microM. The maximum Zn2+ uptake rate (Jmax) of the saturable component was 17 nmol/(mg protein.min). Dietary zinc intake did not affect these parameters. Zn2+ transport by the basolateral membrane may involve an ATP-driven mechanism.
authors.affiliation: Food Science and Human Nutrition Department, University of Florida, Gainesville 32611.
authors.forename: P
authors.initials: P
authors.lastname: Oestreicher
authors.forename: R J
authors.initials: RJ
authors.lastname: Cousins
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002458:Cell Fractionation; D002462:Cell Membrane / Q000378:metabolism; D004032:Diet; D007421:Intestine, Small / Q000378:metabolism* / Q000648:ultrastructure; D007700:Kinetics; D008297:Male; D010042:Ouabain / Q000378:metabolism; D051381:Rats; D012964:Sodium / Q000494:pharmacology; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D015032:Zinc / Q000008:administration & dosage / Q000172:deficiency / Q000378:metabolism*
chemical_list: D010042:Ouabain; D000255:Adenosine Triphosphate; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D015032:Zinc