R Omura

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The anterior semicircular canals of bull frogs were isolated and the cupula was removed from the crista and the sensory cilia on the crista were depressed toward the canal side by a glass micropipette. Seven points on the crista were selected for stimulation. Decremental time constants of the anterior ampullary nerve action potentials were measured. The(More)
The effect of Gentamicin (GM) on the vestibular organ was studied using bullfrogs. The ototoxicity was compared among 3 different ways of administration, i.e., intraperitoneal (IP), intramuscular (IM) and intralabyrinthine (IL) injections. Morphological change of the posterior canal crista was observed by SEM. The posterior canal ampullary nerve action(More)
Eighty micrograms of Gentamicin were injected into bull frogs' perilymphatic cistern for 3 days. Behavioral changes were evaluated together with morphology of the semicircular canal crista and the utricular macula. The behaviors evaluated were posture, walking, head stability, jumping and swimming. The earliest change of behavior was noticed one day after(More)
The posterior semicircular canal of the frog was sinusoidally stimulated by mechanical endolympathic flow. Interaction of the excitatory and the inhibitory responses was analyzed on the spike density histogram. When the oscillation started in ampullofugal direction, the evoked action potentials were readily suppressed by the following ampullopetal stimulus.(More)
The frog Rana nigromaculata was used as an experimental model. The utricle and its nerve were isolated with the anterior and the lateral semicircular canal ampullae in frog Ringer's solution. The utricular otoconia and the otoconial membrane were then carefully removed. The halved anterior canal cupula was next placed in the tip of a glass microelectrode,(More)
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