The effect of prolactin (PRL) on human fetal lung and liver protein synthesis in vitro.

Lung and liver tissue slices from fetuses aborted at 20 weeks gestation were incubated for 8 hours in MEM Eagle's medium containing PRL (85 ng/ml). Protein synthesis and AFP concentrations were measured in the tissue and the incubation medium. The obtained results showed that protein synthesis was reduced by 30% in the lung and by 55% in the liver tissue slices after PRL treatment in vitro. The AFP concentration remained almost unchanged in the lung and was reduced in the liver. Direct evidence that AFP is not synthesized by human fetal lung of 20 weeks gestation was provided from experiments with puromycin. In spite of the strong inhibition of protein synthesis in both fetal lung and liver, AFP concentration was reduced only in liver and remained unchanged in the lung.