ABSTRACT
BACKGROUND AND OBJECTIVES: Fos, the protein product of c-fos gene, has been known to be rapidly expressed in neurons following various external and internal stimuli and this protein expression has been used as a neural activation marker in many fields. This experiment was performed to examine the afferent pathway of the lateral semicircular canals following sinusoidal acceleration. MATERIALS & METHODS: To stimulate the lateral semicircular canals, animals received rotary stimulation for 90 minutes with 2.0Hz sinusoidal acceleration. Thirty minutes after stimulation, the subjects were sacrificed and their brainstems were processed for immunohistochemistry to detect Fos expression. RESULTS: Fos proteins were strongly expressed in the superior, dorsal medial vestibular and inferior vestibular nuclei. However, there was no expression in the lateral and ventral portion of medial vestibular nuclei. CONCLUSION: This finding suggested that the afferent pathway from peripheral vestibular end-organ can be successfully mapped by detection of Fos expression and Fos is an useful neural activity marker in the vestibular system.