Technique for in situ perfusion of the guinea pig placenta

A simple technique is described for perfusing the guinea pig placenta in situ through the umbilical circulation. Flow rates, perfusion pressures, and transplacental electrical potential gradients were maintained for the duration of the perfusions (1--2h) at values reported for the exteriorised fetus. Terminally, the placentae were shown to be uniformly perfused and of normal weight.