Transfer of radioactive iron through the placenta in animals and man
Description
The following results apply to the mammals with haemochorial placenta investigated so far as well as to man: Within a few minutes after injection of radioactive iron compounds into the mother's blood circulation, activity can be verified in the fetus. When several fetuses exist, the degree of activity may vary from one fetus to another. Iron to supply the fetus is not provided by hemoglobin; when it reaches the placental barrier it is bound to beta-globulin. Iron is only transported in the directions from mother to fetus. The concentration of radioactive iron in the fetal serum exceeds that of the mother's serum within minutes of the injection. This presupposes an active transport mechanism at the placenta and the fetus accumulates radioactive iron most of all in the liver; these reserves are formed with a view to compensate low iron supply during lactation. Because in rabbits the greatest number of important parameters was found to be identical with man as regards diaplacental transfer, this species seems to be the most appropriate model to elucidate the diaplacental passage of suitable radionuclide compounds in man. (orig.)
Availability note (English)
Available from Bundesgesundheitsamt, Neuherberg (Germany, F.R.). Inst. fuer Strahlenhygiene.Abstract (German)
Fuer die bisher untersuchten Saeugetiere mit haemochorialer Plazenta und den Menschen gilt: Innerhalb weniger Minuten nach Injektion von radioaktiven Eisenverbindungen in den muetterlichen Kreislauf laesst sich Aktivitaet im Fetus nachweisen. Bei Vorhandensein mehrerer Feten kann die Aktivitaetskonzentration von Fetus zu Fetus variieren. Das Eisen fuer die fetale Versorgung stammt nicht aus dem Haemoglobin, sondern erreicht die Plazentarschranke an Beta-Globulin gebunden. Das Eisen wird nur in der Richtung Mutter-Fetus transportiert. Die Radioeisenkonzentration des fetalen Serums uebersteigt diejenige des muetterlichen schon wenige Minuten nach der Injektion. Dies setzt einen aktiven Transportmechanismus an der Plazenta voraus und Radioeisen reichert sich im Fetus am staerksten in der Leber an, da dort Reserven fuer die eisenarme Laktationszeit angelegt werden. Aufgrund der meisten Uebereinstimmungen in den wichtigsten Parametern, die den diaplazentaren Transfer betreffen, ist das Kaninchen das wohl geeignetste Modell fuer die Klaerung der diaplazentaren Passage geeignete Radionuklidverbindungen beim Menschen. (orig.)Additional details
Additional titles
- Original title (German)
- Diaplazentarer Transfer von Radioeisen bei Tier und Mensch
Publishing Information
- Imprint Pagination
- 36 p.
- Report number
- ISH--15
INIS
- Country of Publication
- Germany
- Country of Input or Organization
- Germany
- INIS RN
- 18008830
- Subject category
- S63: RADIATION, THERMAL, AND OTHER ENVIRONMENTAL POLLUTANT EFFECTS ON LIVING ORGANISMS AND BIOLOGICAL MATERIALS; S63: RADIATION, THERMAL, AND OTHER ENVIRONMENTAL POLLUTANT EFFECTS ON LIVING ORGANISMS AND BIOLOGICAL MATERIALS;
- Resource subtype / Literary indicator
- Non-conventional Literature
- Descriptors DEI
- ANIMALS; FETUSES; HEMOGLOBIN; INTESTINAL ABSORPTION; IRON 55; IRON 59; METABOLISM; PLACENTA; PREGNANCY; RABBITS; RADIONUCLIDE KINETICS; RETENTION; REVIEWS; UPTAKE; WOMEN
- Descriptors DEC
- BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; CARBOXYLIC ACIDS; DAYS LIVING RADIOISOTOPES; DOCUMENT TYPES; ELECTRON CAPTURE RADIOISOTOPES; EVEN-ODD NUCLEI; FEMALES; FETAL MEMBRANES; GLOBINS; HETEROCYCLIC ACIDS; HETEROCYCLIC COMPOUNDS; INTERMEDIATE MASS NUCLEI; IRON ISOTOPES; ISOTOPES; KINETICS; MAMMALS; MAN; MEMBRANES; NUCLEI; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; PIGMENTS; PORPHYRINS; PRIMATES; PROTEINS; RADIOISOTOPES; VERTEBRATES; YEARS LIVING RADIOISOTOPES