Alternative method in experimental ERG for retinal toxicity
We aimed to define a cost-effective and alternative method for experimental electroretinography (ERG) in rabbits. The trigger input port of data acquisition device was connected to output port of an unemployed EEG device. The exposure area of photic stimulator was firmly covered by Wratten neutral density filters with variable optical densities(ODs). Different optical transmissions were obtained by putting more than one filter over the other one. The illumination of the area at the level of rabbit eye was measured by a luminometer in photic stimulations. ERG was performed to the both eyes of three albino rabbits in scotopic and photopic conditions at the baseline. Intravitreal saline injections were performed in right eyes of the rabbits. ERG and ophthalmologic examination were repeated one week later. ERG responses were obtained by short-duration light stimuli with different strengths in scotopic (-2.69; -1.69; 0.00; 0.30; 0.69; 0.90; 1.10; 1.30; 1.69; 2.00 log stimulus energy (log cd.s/m²)) and in photopic conditions (1.3; 1.69; 2.0; 2.10; 2.30 log stimulus energy (log cd.s/m²)). Although minimal decays in amplitudes of a- and b- waves were detected after saline injection, there was no significant difference between baseline and after injection for the stimulus-response time of a- and b- waves (p>0.05). An unemployed EEG device can be effectively used for photic stimulation in experimental ERG in the studies of retinal toxicity.
Keywords:
Electroretinography, photic stimulator, electroencephelography,
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- Yayın Aralığı: Yılda 4 Sayı
- Başlangıç: 1980
- Yayıncı: Ondokuz mayıs Üniversitesi Tıp Fakültesi