Neurogenesis and astrogenesis contribute to vestibular compensation in the neurectomized adult cat: cellular and behavioral evidence

Neurogenesis occurs in some regions of the adult mammalian brain and gives rise to neurons integrated into functional networks. In pathological or postlesional conditions, neurogenesis and astrogenesis can also occur, as demonstrated in the deafferented vestibular nuclei after unilateral vestibular neurectomy in the adult cat. Here we report that in cats infused with an antimitotic drug, cytosine-ß-D arabinofuranoside (AraC), the number of GAD67 and GFAP immunoreactive cells is increased, despite the total mitotic activity blockade observed in the deafferented vestibular nuclei after unilateral vestibular neurectomy. At the behavioral level, recovery of posturo-locomotor function was drastically delayed, and no alteration of the horizontal spontaneous nystagmus was observed. These cellular and behavioral results suggest that reactive neurogenesis and astrogenesis might contribute highly to vestibular compensation in the adult cat, probably by accelerating the recovery of vestibular functions.