[Effect of hyaluronan perfusion through the round window on the function and morphology of the inner ear in guinea pigs].
In order to study the effect of the hyaluronan (HA) on the inner ear, twenty-six guinea pigs were divided into experimental and control groups, the experimental group were perfused with 2% HA 0.2 ml through the left round window. Auditory and vestibular function were investigated before and 5, 14, 28 days after perfusion. The threshold of action potential (AP) response to filtered clicks (0.25-10 kHz) were elevated at 5 days and were improved (at 1-4 kHz) at 14 days after perfusion (P < 0.05). At 28 days all AP response thresholds had returned to normal (P > 0.05). The nystagmus duration induced by caloric test (ENG) had no obviously change comparing with that of preoperation (P > 0.05). All guinea pigs were sacrificed 28 days after operation. The histology of inner ear were examined by means of membranous labyrinth mapping and temporal bone section after celloidin embedding. The morphology of Corti's and vestibular organs were not significantly damaged after perfusion.


CONCLUSIONS
1) 2%HA caused reversible and temporary changes in auditory function of inner ear; 2) 2%HA lacked ototoxic adverse effects, whereas exerted considerable osmotic effects and a slow dehydration of inner ears.
Yin
T
T
Second Clinical College, Hunan Medical University, Changsha.
Lu
Y
Y
Chen
Z
Z
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D001300:Audiometry, Evoked Response; D007758:Ear, Inner / Q000187:drug effects / Q000502:physiology*; D004584:Electronystagmography; D005260:Female; D006168:Guinea Pigs; D006820:Hyaluronic Acid / Q000494:pharmacology*; D008297:Male; D010477:Perfusion; D011897:Random Allocation; D012405:Round Window, Ear / Q000502:physiology
D006820:Hyaluronic Acid