Chronic GM₁ ganglioside treatment reduces dopamine cell body degeneration in the substantia nigra after unilateral hemitransection in rat

The effect of GM₁ gangliosise on the recovery of dopaminergic nigro-striatal neurons was studied in rats after unilateral hemitransection. GM₁ treatment partially prevented the decrease of tyrosine hydroxylase (TH) activity caused by hemitransection in the substantia nigra ipsilateral to the lesion. Concimitantly a significant increase of TH-immunoreactivity in the substantia nigra was also detected. In particular, chronic treatment with GM₁ prevented the disappearance of TH-positive cell bodies in the substantia nigra and induced the appearance of longer TH-positive dendrites with respect to the saline treatment. These data indicate that GM₁ treatment maintains the number of dopaminergic cell bodies in the substantia nigra after hemitransection by protecting against retrograde neuronal degeneration.