Fos Expression in the Rat Vestibular Nucleus Complex after Plugging the Three Semicircular Canals

Abstract

Hypothesis: Differential compensation after unilateral semicircular canal plugging (UCP) and unilateral labyrinthectomy (UL) may involve different expression patterns of fos mRNA and Fos protein in the vestibular nucleus complex. Background: The expression of Fos protein in the vestibular nuclei underwent spatiotemporal changes related to the compensation process following surgical UL and chemical UL. These changes were temporally related to the appearance and development of vestibular compensation in the rat. Methods: Spatiotemporal changes in both fos mRNA and protein levels in the rat brain after UCP were observed. The Fos expression pattern after UCP was compared to that after UL. Results: Greater fos mRNA and Fos protein expressions were detected in bilateral medial vestibular nuclei (MVNs) after UL than after UCP. The changes were relatively long-lived after UL compared to those following UCP. Conclusion: Differences in the expression pattern of fos mRNA and Fos protein in bilateral MVNs between UCP and UL may explain differences in compensation after UCP and UL.