Manganese uptake into rat brain during development and aging

Abstract

Manganese (Mn) is an essential metal and plays an important role in the brain. To evaluate Mn uptake into the brain during development and aging, 54Mn concentrations in the brain of rats aged from 5 days to 95 weeks were measured after injection of 54MnCl2. 54Mn concentration in the brain of 5-day-old rats was the highest of all age groups tested. The liver and blood of 5-day-old rats also showed the highest 54Mn concentrations among the age groups. These results suggest that Mn is required in a high amount during infancy and that a sufficient Mn supply is critical for normal brain development. The high uptake of Mn into the brain of neonatal rats may be due to high levels of Mn in the blood, which may be supplied from the liver. In the 5-day-old brain, 54Mn was relatively concentrated in the hippocampal CA3 and dentate gyrus and the pons. In the aging brain, 54Mn was relatively concentrated in the inferior colliculi, olivary nuclei and red nuclei.

Analysis of Brain Function and Prevention of Brain Diseases: the Action of Trace Metals

“…70,77) The radioactivity from transferrin-bound 54 Mn in the brain was the lowest of all three substrates. Transferrin receptors are present on the surface of brain capillary endothelial cells.…”

“…70) Dietary manganese deficiency might affect manganese homeostasis in the brain, as evidenced by increased susceptibility of manganese-deprived rats to convulsions. 71) Carl et al indicated that manganese concentrations in tissues including the brain are increased after epileptic seizures.…”

Macro- and microelements in the brains of fetuses and newborns in normal and pathological states: A review

“…This element is very important for the normal functioning of the nervous system [16,[34][35][36]. The enzymes that contain magnesium provide energy and plastic processes in the CNS, participate in ATP hydrolysis, maintain the activities of Mg,Ca ATPases, and are involved in the synthesis of neuropeptides [21,37,38].…”

Manganese: Brain Transport and Emerging Research Needs

“…Collectively, transport studies suggest that MnCI2 enters the brain from the blood either across the cerebral capillaries and/or the cerebrospinal fluid (CSF). At normal plasma concentrations, Mn enters the CNS primarily across the capillary endothelium, whereas at high plasma concentrations, transport across the choroid plexus predominates (14,(29)(30)(31)(32)(33).…”

“…For example: a) both metals are transition elements adjacent to each other in the Periodic Table; b) both carry similar valence charges (2+ and 3+) in physiological conditions; c) both have similar ionic radius; d) both strongly bind Tf (3,14,22), and e) intracellularly, both preferentially accumulate in mitochondria (43,44 …”