Glutathione peroxidase activity and chemical forms of selenium in tissues of rats given selenite or selenomethionine

Journal Article · Sun May 01 00:00:00 EDT 1988 · J. Inorg. Biochem.; (United States)

DOI:https://doi.org/10.1016/0162-0134(88)80032-1· OSTI ID:6855922

Beilstein, M A; Whanger, P D

Glutathione peroxidase (GPx) activity and deposition of selenium (Se) were examined in tissues of rats given dietary Se for 7 wk as either selenite or selenomethionine (SeMet) with 75Se radiotracer of the same chemical form. On the basis of Se:75Se ratio, all tissues of the rats fed selenite were equilibrated with the dietary source, but tissues of the SeMet fed animals maintained a ratio of Se:75Se greater than the dietary ratio. Deposition of dietary Se and 75Se was higher in most tissues of rats fed SeMet. Muscle 75Se was the largest single tissue pool of 75Se in both groups accounting for one-third of recovered 75Se in the rats fed selenite, and one-half of recovered 75Se in the rats fed SeMet. Tissue GPx activities were not different between the two dietary groups. The proportion of Se as GPx in tissues was highest in erythrocytes of the rats fed selenite (.81) and lowest in testes and epididymides of the rats fed SeMet (.009). The proportion of Se present in cytosolic GPx was consistently higher in tissues of rats fed selenite. Erythrocytes of the rats fed SeMet had more 75Se associated with hemoglobin, and muscle cytosols of the rats fed selenite had more 75Se associated with the G-protein. The proportion of 75Se as SeMet determined by ion exchange chromatography of tissue hydrolysates was higher in tissues of rats fed SeMet (highest in muscle and hemoglobin, 70%, and lowest in testes, 16%). In contrast, selenocysteine was the predominant form of Se present in tissues of rats given selenite. These results indicate that the form of Se administered will influence the form in the tissues, the percentage of Se with GPx and the body burden of Se.

• Research Organization: Oregon State Univ., Corvallis (USA)
• OSTI ID: 6855922
• Journal Information: J. Inorg. Biochem.; (United States), Vol. 33:1
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
PEROXIDASES
ENZYME ACTIVITY
SELENIUM
METABOLISM
TISSUE DISTRIBUTION
BODY BURDEN
ION EXCHANGE CHROMATOGRAPHY
RATS
SELENIUM 75
TRACER TECHNIQUES
ANIMALS
BETA DECAY RADIOISOTOPES
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
DISTRIBUTION
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
ENZYMES
EVEN-ODD NUCLEI
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
NUCLEI
OXIDOREDUCTASES
RADIOISOTOPES
RODENTS
SELENIUM ISOTOPES
SEMIMETALS
SEPARATION PROCESSES
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology
550501 - Metabolism- Tracer Techniques