Down syndrome is determined by the presence of an extra copy of autosome 21 and is expressed by multiple abnormalities, with mental retardation being the most striking feature. The condition results in altered electrical membrane properties of fetal dorsal root ganglia (DRG) neurons, as in the trisomy 16 fetal mouse, an animal model of the human condition. Cultured trisomic DRG neurons from human and mouse fetuses present faster rates of depolarization and repolarization in the action potential compared to normal controls and a shorter spike duration. Also, trisomy 16 brain and spinal cord tissue exhibit reduced acetylcholine secretion. Therefore, we decided to study Ca2+ currents in cultured DRG neurons from trisomy 16 and age-matched control mice, using... |