ABSTRACT
Transport dynamics in the human placental lobule have been investigated in vitro using a dual perfusion technique. Buffered oxygenated Earle's salt solution was used as the perfusate. Dynamic transport function was studied by the use of novel transport parameters in short-term experiments of 5 min duration. Differential transport rates of tritiated water averaged 0.42, 1.05 and 2.68 min, respectively, for 10, 50 and 90% of radioactivity efflux in the fetal vein in 5 perfusions. Inulin radioactivity was not detected in the fetal vein in any of the 5 experiments, indicating the absence of transport in our perfusion conditions. It is concluded that the new parameters employed could be used successfully for studying transport dynamics using varying reference substances and in different experimental conditions or pathological states
Subject(s)
Insulin , Maternal-Fetal ExchangeABSTRACT
The effect of a reduction in maternal perfusate flow on maternal-fetal transport of urea and antipyrine has been investigated in vitro using the isolated human placental lobule. The protocol was so designed that the same lobule served as its own control for the study. On reducing the maternal perfusate flow to about half of the control value, mimicking a 'toxemia' situation, urn transport rose significantly to about twice the control level while antipyrine transport remained unchanged. The high wrea transport in the simulated toxemia model is in accord with data obtained earlier from preeclamptic pregnancies