Seminars & Events
Thursday, September 11, 2014: Dr. Bevil Conway (Wellesley College) will speak on his research in visual neuroscience and color at 4:30 pm in Goodpaster Hall 195.
Monday, October 27, 2014: Dr. Todd Gould (University of Maryland Baltimore) will speak on "Genes to behaviors to treatments in bipolar disorder" at 4:45 pm in Goodpaster Hall 195.Friday, December 5, 2014: Dr. Brian Mathur (University of Maryland Baltimore) will speak on "Braking bad: Aberrant inhibitory neurotransmission in addiction" at 3:00 pm in Goodpaster Hall 195.
Ramcharitar, J.U., Smist, M.C., Selckmann, G.M., and Traven, S.A. (2009, October). Effects of gentamicin on the goldfish auditory system. Poster presented at the Society for Neuroscience Annual Meeting, Chicago, IL.
Over the last few years, the zebrafish lateral line system has been successfully adopted for the study of pharmaceutical agents known to be ototoxic and otoprotective in humans. However, relatively few investigations have examined ototoxicity in the auditory systems of fishes. As such, we assessed the effects of gentamicin on both the structure and function of the goldfish inner ear, which has a similar configuration to that of the zebrafish. Specifically, changes in sensory hair cell densities of the otolithic end organs (i.e. saccule, lagena and utricle), as well as in auditory evoked potentials (AEPs) were quantified after the administration of gentamicin. Fish were injected once per day (100 mg/kg) for four consecutive days and one day after the final injection, AEPs were determined for the frequency range 100 - 1000 Hz. Fish were then euthanized, fixed overnight with 2.5% glutaraldehyde and auditory epithelia were harvested after washing the tissues with phosphate buffer. Phalloidin was used to visualize ciliary bundles with conventional fluorescence microscopy. All of the treated fish selected for this study demonstrated behavioral deficits including vestibular and feeding problems. Significant reductions in hair cell densities in the striola regions of utricles and lagenae were observed (n = 7, p < 0.05). In this regard, striola hair cells have previously been described as Type I-like. Hair cell ciliary bundle loss was also observed in saccular sensory epithelia. With regard to auditory function, auditory thresholds were found to be elevated in injected fish, indicating that hearing was adversely affected by gentamicin. These data support the use of the teleost inner ear for the screening of new drugs for potential ototoxicity. We also demonstrated that AEP measurements offer rapid assessment of ototoxic effects in a model fish species.