The Effect of Flunarizine and Nimodipine on Rotatory Evoked Potentials in Rabbit

Abstract

Rotatory evoked potentials were recorded in 6 normal albino rabbits before and after administration of flunarizine and nimodipine. Latencies of REP were unchanged by the Ca-antagonists whereas their amplitudes showed some characteristic alterations. There was a significant lowering of amplitude in those peaks which had previously been shown to be of vestibular origin. The peaks that reflect somatosensory activity were amplified by the drugs. Flunarizine showed a more marked effect on the vestibular part of the response than nimodipine. A selective action of Ca-antagonists on brainstem nuclei is suspected.

Key Words:

• vestibular evoked potentials
• labyrinthectomy
• deceleration stimuli
• somatosensory afferences
• Ca-antagonists
• brainstem nuclei
• vertigo