Modifications in perineuronal nets of rat vestibular nuclear neurons during postnatal development and in injury

Abstract

Perineuronal net (PN), the extracellular matrix around neurons, has been shown to be involved in neural plasticity. To determine if PN in the vestibular nuclei (VN) plays any role on plastic change of central vestibular network, we studied PN in two states of functional modifications in the vestibular system which are postnatal development of VN and compensation of VN neuronal activity after unilateral labyrinthectomy (UL). Staining with lectin WFA was used to identify PN around VN neurons. In postnatal VN, fuzzy PN was detectable by P3. They became consolidated from P9 onwards. The number of VN neurons with PN also increased with age, reaching adult level by P21. With UL, the PN on the lesioned side of adult rats became fuzzy at 3–5 days post-lesion but resumed normal by 11–14 days after UL. PN on the labyrinth-intact side, however, showed the compact network. Our findings suggest that structural changes of PN around VN neurons contribute to plasticity of central vestibular system.