J. Neurochem. (2009) 109, 879–888. The ability of aluminium to affect the oxidant status of specific areas of the brain (cerebellum, ventral midbrain, cortex, hippocampus, striatum) was investigated in rats intraperitoneally treated with aluminium chloride (10 mg Al³⁺/kg/day) for 10 days. The potential of aluminium to act as an etiological factor in Parkinson’s disease (PD) was assessed by studying its ability to increase oxidative stress in ventral midbrain and striatum and the striatal dopaminergic neurodegeneration induced by 6‐hydroxydopamine in an experimental model of PD. The results showed that aluminium caused an increase in oxidative stress (TBARS, protein carbonyl content, and protein thiol content) for most of the brain regions studied, which was accompanied by a decrease in the activity of some antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase). However, studies in vitro confirmed the inability of aluminium to affect the activity of those enzymes. The reported effects exhibited a regional‐selective behaviour for all the cerebral structures studied. Aluminium also enhanced the ability of 6‐hydroxydopamine to cause oxidative stress and neurodegeneration in the dopaminergic system, which confirms its potential as a risk factor in the development of PD.

A prospective study of patients diagnosed with ‘single-canal' benign paroxysmal positional vertigo (BPPV) was performed. Demographic, etiological and prognostic differences between patients with posterior, horizontal and superior canal BPPV were studied. A total of 614 patients diagnosed in a period of 11 years and with a follow-up period of at least 1 year were included in the study. The posterior semicircular canal was affected in 543 casas (88.4%), the horizontal in 39 (6.4%) and the superior canal in 32 (5.2%). Final status at the end of the follow-up period was better in posterior canal BPPV (95% cure) than in horizontal or superior canal BPPV (87% cure in both cases). This may be explained by two facts: a poorer initial response to repositioning maneuvers in anterior canal BPPV than in BPPV involving the other two canals, and a poorer response to maneuvers in recurrences of horizontal canal BPPV.