Quantitative studies on aluminum deposition and its effects on neurofilament protein expression and phosphorylation, following the intraventricular administration of aluminum maltolate to adult rabbits.

The deposition of aluminum (Al) in the brain and spinal cord of adult male New Zealand white rabbits was monitored following the intraventricular administration of Al maltolate. Although decreasing concentrations of Al were observed from the injection site (approximately 10 micrograms/g dry tissue) to the lumbar cord (2.1 micrograms/g), argyrophilic tangles were present in the perikarya and proximal neurites of neurons as far distal as the lumbar and sacral cord areas. Quantitative immunoblot studies of the three neurofilament protein isoforms failed to detect changes resulting from Al maltolate treatment. Similarly no significant alterations in the total phosphate content of these cytoskeletal proteins were observed. Lastly, on Northern blots, the expression of genes encoding for the 200 kDa and 68 kDa neurofilament proteins also was unaffected by Al maltolate treatment.