Gamma camera imaging for studying intestinal absorption and whole-body distribution of selenomethionine.
Se metabolism in humans is not well characterised. Currently, the estimates of Se absorption, whole-body retention and excretion are being obtained from balance and tracer studies. In the present study, we used gamma camera imaging to evaluate the whole-body retention and distribution of radiolabelled selenomethionine (SeMet), the predominant form of Se present in foods. A total of eight healthy young men participated in the study. After consumption of a meal containing 4 MBq [⁷⁵Se]L-SeMet ([⁷⁵Se]SeMet), whole-body gamma camera scanning was performed for 45 min every hour over a 6 h period, every second hour for the next 18 h and once on each of the subsequent 6 d. Blood, urine and faecal samples were collected to determine the plasma content of [⁷⁵Se]SeMet as well as its excretion in urine and faeces. Imaging showed that 87·9 (sd 3·3)% of the administered activity of [⁷⁵Se]SeMet was retained within the body after 7 d. In contrast, the measured excretion in urine and faeces for the 7 d period was 8·2 (sd 1·1)% of the activity. Time-activity curves were generated for the whole body, stomach, liver, abdomen (other than the stomach and the liver), brain and femoral muscles. Gamma camera imaging allows for the assessment of the postprandial absorption of SeMet. This technique may also permit concurrent studies of organ turnover of SeMet.
Department of Clinical Physiology and Nuclear Medicine, Centre of Functional Imaging and Research, Hvidovre Hospital, Kettegård Allé 30, DK-2650 Hvidovre, Denmark.
Jan L
JL
Madsen
Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden.
Katarina
K
Sjögreen-Gleisner
Hevesy Laboratory, Technical University of Denmark, DTU Nutech, Roskilde, Denmark.
Dennis R
DR
Elema
Department of Clinical Physiology and Nuclear Medicine, Centre of Functional Imaging and Research, Hvidovre Hospital, Kettegård Allé 30, DK-2650 Hvidovre, Denmark.
Lasse R
LR
Søndergaard
Hevesy Laboratory, Technical University of Denmark, DTU Nutech, Roskilde, Denmark.
Palle
P
Rasmussen
Department of Clinical Physiology and Nuclear Medicine, Centre of Functional Imaging and Research, Hvidovre Hospital, Kettegård Allé 30, DK-2650 Hvidovre, Denmark.
Stefan
S
Fuglsang
Department of Medical Radiation Physics, Clinical Sciences, Lund University, Lund, Sweden.
Michael
M
Ljungberg
Department of Clinical Physiology and Nuclear Medicine, Centre of Functional Imaging and Research, Hvidovre Hospital, Kettegård Allé 30, DK-2650 Hvidovre, Denmark.
Morten
M
Damgaard
D000328:Adult; D005243:Feces / Q000737:chemistry; D015902:Gamma Cameras; D006801:Humans; D007408:Intestinal Absorption; D008297:Male; D008954:Models, Biological; D019518:Postprandial Period; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D012643:Selenium / Q000378:metabolism*; D012644:Selenium Radioisotopes; D012645:Selenomethionine / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D014018:Tissue Distribution; D051598:Whole Body Imaging
D019275:Radiopharmaceuticals; D012644:Selenium Radioisotopes; D012645:Selenomethionine; D012643:Selenium