Effects of Amphetamine and Diazepam on the Vestibuloocular Reflex in Rabbits

家兎의 前庭眼球反射에 대한 Amphetamine 및 Diazepam의 影響

The effects of amphetamine and diazepam on the control of body posture were examined in unanesthetized rabbits. Vestibuloocular reflex(VOR) was elicited by rotation of whole body at frequency of 0.1, 0.2, 0.3Hz by means of sinusoidal rotator in the dark. The following results were obtained. 1) In normal VOR, the frequency and the velocity of nystagmus were increased by increasing the frequency of stimulus rotation from 0.1Hz to 0.3Hz. 2) In amphetamine treated VOR, the frequency and the velocity of nystagmus were increased at all of 3 stimulus frequencies, but any significant differences of the velocity of nystagmus between different stimulus frequencies were not observed. 3) In diazepam treated VOR, the frequency and the velocity of nystagmus were decreased at all of 3 stimulus frequencies, but any significant differences of the frequency and the velocity of nystagmus between different stimulus frequencies were not observed. 4) The actions of amphetamine and diazepam on the VOR were contradictory. These data suggest that amphetamine and diazepam may impair the control of body posture by increasing or decreasing the VOR respectively, through their action on the central nervous system but not on the vestibular system.