Transferrin in fetal rat brain and cerebrospinal fluid

Concentrations of transferrin in plasma, cerebrospinal fluid (csf) and brain of fetal and newborn rats have been estimated by radial immunodiffusion assay. Transferrin was detected in both csf and brain at the earliest age investigated (12 days gestation). The plasma concentration increased throughout the gestational period studied and in the postnatal period: the overall increase was about 10-fold. In contrast, although the csf transferrin concentration increased by 3 times between 12 and 22 days (term) there was a considerable decline on reaching adult age. Brain transferrin concentration was highest at 18 days gestation. These results are important background information for studies of the significance of transferrin in brain development.