Effect of tryptophan on livers of pregnant and lactating rats and their fetuses and pups. 
The effect of the administration of L-tryptophan on hepatic polyribosomes and protein synthesis in pregnant rats and their fetuses and in lactating rats and their pups was investigated.  Pregnant rats tube-fed tryptophan 1 hr before killing revealed increased hepatic protein synthesis but essentially unmodified polyribosomal aggregation of maternal livers while no changes were observed in fetal livers in comparison to controls (water-treated).  Lactating rats tube-fed tryptophan 1 hr before killing revealed increased polyribosomal aggregation and protein synthesis of the livers in comparison to controls.  Pups of these mothers that received tryptophan intraperitoneally 1 hr before killing did not reveal a significant change in the hepatic polyribosomes or protein synthesis.