查看文章

Materials and Methods

The dual perfusion of an isolated human placental lobule was adapted from Wier et al.[1983b], as modified from the original work of Panigel [1962] and Schneider et al.[1972]. The placentas were obtained from patients requiring repeat cesarian section at term. The perfusates consisted of tissue culture medium M199 (Difco, Detroit) with heparin (25 IU/ml, AH Robbins), glucose (2.0 g/1), dextran 40 (fetal: 30 g/1, maternal: 7.5 g/1, Sigma), and gentamicin (50 mg/1, AH Robbins). The fetal perfusate was gassed with 95% 12/5% CO2 and recirculated following the collection of the first 30 ml of perfusate. The maternal perfusate was gassed with 95% O2/5% CO2 and also recirculated following the collection of the first 30 ml of perfusate. The fetal flow rate was 3.0-3.5 ml/mm, and the maternal flow rate was 15-25 ml/min. The recirculating volumes for maternal and fetal circuits were 170 and 60 ml …