Rapid screening assay for calcium bioavailability studies

Conference · Sat Mar 01 04:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5384498

Luhrsen, K R; Hudepohl, G R; Smith, K T

Calcium bioavailability has been studied by numerous techniques. The authors report here the use of the gamma emitting isotope of calcium (/sup 47/Ca) in a whole body retention assay system. In this system, calcium sources are administered by oral gavage and subsequent counts are determined and corrected for isotopic decay. Unlike iron and zinc retention curves, which exhibit a 2-3 day equilibration period, calcium reaches equilibration after 24 hours. Autoradiographic analysis of the femurs indicate that the newly absorbed calcium is rapidly distributed to the skeletal system. Moreover, the isotope is distributed along the entire bone. Comparisons of calcium bioavailability were made using intrinsic/extrinsic labeled milk from two species i.e. rat and goat as well as CaCO/sub 3/. In addition, extrinsic labeled cow milk was examined. In the rat, the extrinsic labeled calcium from milk was better absorbed than the intrinsic calcium. This was not the case in goat milk or the calcium carbonate which exhibited no significant differences. Chromatographic analysis of the labeled milk indicates a difference in distribution of the /sup 47/Ca. From these data, the authors recommend the use of this assay system in calcium bioavailability studies. The labeling studies and comparisons indicate caution should be used, however, in labeling techniques and species milk comparison.

• Research Organization: Procter and Gamble Co., Cincinnati, OH
• OSTI ID: 5384498
• Report Number(s): CONF-8604222-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:3
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METALS
ANIMALS
AUTORADIOGRAPHY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOASSAY
BIOLOGICAL AVAILABILITY
BIOLOGICAL MATERIALS
BODY
BODY FLUIDS
CALCIUM
CALCIUM 47
CALCIUM ISOTOPES
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
DOMESTIC ANIMALS
ELEMENTS
EVEN-ODD NUCLEI
FEMUR
FOOD
GOATS
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
MATERIALS
METALS
MILK
NUCLEI
ORGANS
RADIOISOTOPES
RATS
RETENTION
RODENTS
RUMINANTS
SEPARATION PROCESSES
SKELETON
TRACER TECHNIQUES
VERTEBRATES