UPTAKE OF NICKEL INTO THE BRAIN VIA OLFACTORY NEURONS IN RATS

Intranasal instillation of nickel (Ni-63(2+)) in rats resulted in an u ptake of the metal in the olfactory epithelium and a migration along p rimary olfactory neurons to the glomeruli of the olfactory bulb. The m etal was then seen to pass to the interior of the bulb and further to the olfactory peduncle, the olfactory tubercle and the rostral parts o f the prepiriform, frontal and cingulate corticis. These results indic ate that Ni-63(2+) slowly passes to secondary and tertiary olfactory n eurons. Intraperitoneal injection of Ni-63(2+) resulted in a low uptak e in the brain, without preferential labelling of the olfactory pathwa ys. Inhalation of nickel compounds can impair the olfactory system. An uptake of nickel in the olfactory neurons may underly these lesions. (C) 1997 Elsevier Science Ireland Ltd.