The effect of the glutamate antagonist CNQX (6-cyano-7-nitroquinoxaline-2,3dione) on Off-bipolar cells in the zebrafish (Dania reria) was examined. CNQX has suppressed the d-wave component of electroretinogram (ERG) in other species. Here, adult zebrafish received an injection ofCNQX or saline solution. They were then presented 200 ms stimuli at 17 wavelengths and several irradiances. Spectral sensitivity was calculated from the b-wave components ofthe ERG responses. Retinal injection of CNQX impacted the a-, b-, and d-waves ofthe ERG, especially at longer wavelengths. Significant differences in the spectral sensitivity functions of the CNQX and saline groups were found at 460 nm and 540 urn-the location ofM - Sand L - M color opponent mechanisms; thus, CNQX suppresses the color-opponent mechanisms. The fact that CNQX selectively affects sensitivity at longer wavelengths supports the presence of multiple Off-bipolar cell types. This study sought to further clarify the specificity of Off-bipolar cells and the general visual pathway of the adult zebrafish.
Advisor(s) or Committee Chair
Dr. Joseph Bilotta
Au, Margaret G., "Zebrafish cone contributions and ERG waveforms as impacted by CNQX" (2004). Mahurin Honors College Capstone Experience/Thesis Projects. Paper 182.