MANGANESE TRANSPORT ACROSS THE BLOOD-BRAIN-BARRIER - RELATIONSHIP TO IRON HOMEOSTASIS

The binding characteristics of manganese (Mn) to transferrin (Tf) were examined on G-75 Sephadex gel columns. When 54MnCl2 was combined with Tf and immediately fractionated on the Sephadex column, 49% of 54Mn was bound to Tf. The fraction of 54Mn which was Tf-bound was dependent upon the incubation period, and increased in a time-dependent fashion. In vivo, 6 hr of intravenous administration of ferric-hydroxide dextran complex significantly inhibited (p<0.05)54Mn brain uptake as compared to its uptake in iron-free dextran-treated rats. These results suggest that iron (Fe) homeostasis may play an important role in the regulation of Mn transport across the blood-brain barrier (BBB). © 1990.