Transport kinetics of zinc, copper, selenium, and iron in perfused human placental lobule in vitro.
Mol Cell Biochem
; 252(1-2): 91-6, 2003 Oct.
Article
em En
| MEDLINE
| ID: mdl-14577580
ABSTRACT
Transport characteristics of essential trace elements as zinc, copper, selenium and iron have been studied in maternal-fetal direction in normal pregnancies, using in vitro perfusion of human placental lobules. Solutions of trace elements corresponding to twice the physiological concentrations were injected (100 microl bolus) into the maternal arterial perfusate. Serial perfusate samples were collected every 30 sec from venous outflows for a study period of 5 min. Concentrations of these trace elements and their transport kinetics were determined. Transport fractions (TF) of zinc, copper, selenium and iron averaged 0.21, 0.49, 0.55 and 0.10% of maternal load respectively. Other parameters such as area under the curve, clearance, elimination constant, absorption and elimination rates showed some significant differences between the various elements. Copper and selenium appear to be transported passively in maternal-fetal direction, while for iron and zinc, role of active transport for transfer across the human placental membrane cannot be discounted. We speculate that alterations in copper zinc TR50 (transport rate for 50% efflux) and TF ratios could serve as useful indicators for assessing placental transport status of these essential elements in complicated pregnancy states.
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Base de dados:
MEDLINE
Assunto principal:
Placenta
/
Selênio
/
Zinco
/
Cobre
/
Ferro
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Mol Cell Biochem
Ano de publicação:
2003
Tipo de documento:
Article