St. Mary's College of Maryland

Seminars & Events

Monday, February 11, 2013: Dr. Daphne Soares (University of Maryland College Park) will speak on "The Sensory World of Cavefishes" at 4:45 pm in Goodpaster Hall 195.

Monday, March 4, 2013: Dr. Joe Cheer (University of Maryland Baltimore) will speak on "Endogenous Cannabinoids and the Pursuit of Reward" at 4:45 pm in Goodpaster Hall 195

Friday, April 12, 2013:  Dr. Jill McGaughy (University of New Hampshire) will speak on "The Role of Cortical Norepinephrine in the Ontogeny of Executive Function" at 3:00 pm in Schaefer Hall 106.

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Alumni Highlight

Erin Johnson inducted as an Alumni Member of Nu Rho Psi

Dr. Erin Johnson '02 recently received her Ph.D. in Neuroscience from the University of Rochester School of Medicine, and was inducted as an alumni member of Nu Rho Psi.

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SMP Spotlight

Students on SMP Presentation Day

Ron Saul, "Chronic activation of the substantia nigra nociceptin/orphanin receptor induces motor deficits similar to Parkinson's disease," 2008. Saul, the 2008 winner of the Neuroscience Award, infused a drug into the substantia nigra of rats and measured the resulting motor behaviors, mood disturbances, and cognitive abilities.

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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.

Abstract 

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.

Aerial view of St. Mary's College of Maryland campus

St. Mary's College of Maryland
18952 E. Fisher Rd
St. Mary's City, MD 20686-3001
240-895-2000