title: Development of a technique for in situ studies of calcium absorption in the intestine of rats.
abstract: The aim of the present study was to develop (feasibility, reliability, reproducibility) a technique for the in situ measurement of intestinal calcium absorption in the rat. An intestinal loop (duodenum+proximal jejunum) was perfused both by the intraluminal and vascular routes. A solution of NaCl 155 mM and CaCl2 1.25 mM containing 45Ca was perfused intraluminally at a flow rate of 0.2 ml/min and the 45Ca appearing in the venous effluent was determined to estimate calcium absorption. This technique was used to study the effect of a 10-day period of calcium supplementation on calcium absorption. The animals received enterally either 5 or 30 mg/day per kg BW. The results showed that intestinal calcium transport was enhanced when rats were given the calcium supplement for 10 days prior to the experiment (99.3 +/- 2.5 (n = 5) versus 36.6 +/- 3.6 (n = 5) nmol/min per kg BW, P < 0.001). This study indicates that dietary calcium supplement enhances calcium absorption probably by increasing the passive transport of calcium in the small intestine.
authors.affiliation: Unité de Biologie Cellulaire et Physiologie Digestives, INSERM U61, Strasbourg, France.
authors.forename: R
authors.initials: R
authors.lastname: Schleiffer
authors.forename: M
authors.initials: M
authors.lastname: Galluser
authors.forename: O
authors.initials: O
authors.lastname: Rohr
authors.forename: F
authors.initials: F
authors.lastname: Raul
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002136:Calcium, Dietary / Q000494:pharmacology; D007408:Intestinal Absorption / Q000187:drug effects; D008297:Male; D008722:Methods; D051381:Rats; D017208:Rats, Wistar
chemical_list: D002136:Calcium, Dietary; D002118:Calcium