Behavioural recovery from unilateral vestibular lesion is facilitated by GM1 ganglioside treatment.

Exogenously administered gangliosides function in vivo to facilitate survival and repair of damaged neurones in both central and peripheral nervous systems. These effects have been attributed to their neuritogenic and neuronotrophic properties. In this investigation the effects of ganglioside treatment have been studied on the compensation that follows a unilateral labyrinthectomy, considering that the vestibular recovery is supposed to be achieved through a mechanism of sprouting acting on the deafferented neurones. Hemilabyrinthectomized guinea pigs were given a daily injection of either GM1 ganglioside (30 mg/kg, i.p.) or saline for 21 days. As regards postural symptoms, the GM1 group more quickly restored a posture of the head non-deviated in the horizontal plane, while the remaining postural symptomatology was not significantly affected by the treatment. Furthermore, the GM1-treated group attained more rapidly an ocular position characterized by very slow drifts (or by no drift at all), directed towards the side of the intact labyrinth. Ganglioside treatment did not reduce the severity of the initial hemilabyrinthectomy impairments and the effect of the treatment became evident with time. This result is consistent with the hypothesis that also in this model of neuronal plasticity, gangliosides act by enhancing reactive synaptogenesis on the deafferented vestibular neurones.