Retinal cholinergic and dopaminergic deficits of aged rats are improved following treatment with GM1 ganglioside

Selected cholinergic and dopaminergic markers were compared in the retina o f aged (20-22-months-old) and young (3-months-old) rats before and after tr eatment with GM1 ganglioside. The dopaminergic markers, tyrosine hydroxylas e, aromatic L-amino acid decarboxylase, dopamine, 3,4-dihydroxyphenylacetic acid and homovanillic acid were comparable in the young and aged animals a nd GM1 treatment did not alter them. In contrast, mazindol binding, a marke r fur the dopamine transporter, was diminished in the aged retina and treat ment with GM1 restored binding to values found in the young animals. The ch olinergic markers choline acetyltransferase and hemicholinium-3 binding, a marker for the high-affinity choline transport, were depressed in aged rats and GM1 corrected the deficits. (C) 2000 Elsevier Science B.V. All rights reserved.