Interaction of photoreceptor-driven signals in the mouse electroretinogram

• Applicant: Professor Dr. Jan Kremers
• Subject Area: Molecular Biology and Physiology of Neurons and Glial Cells ; Ophthalmology
• Term: from 2020 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 441414098

• Final Report Year: 2024

Final Report Abstract

In the finalized project, the interactions of signals, originating in the different photoreceptors, were studied with electroretinography (ERG) that can be obtained in vivo and non-invasively. To stimulate the photoreceptors in isolation or simultaneously with pre-defined strengths, the silent substitution method was used. To increase the dynamic range of the stimuli, we performed the experiments with LIAIS mice, where the native M-cone pigment is genetically replaced by the human L-cone pigment, so the spectral separation with the other photoreceptors (rods and S- cones) is significantly increased. LIAIS mice are otherwise normal. The silent substitution methods can be combined with repetitive temporal stimulus profiles. Particularly the white noise stimulus is powerful to characterize the ERG responses. In addition, the state of adaptation for each photoreceptor type can be, within the gamut of the stimulator, chosen independently. In the project, we studied the responses to white noise stimulation of all photoreceptors simultaneously or each separately at different mean luminance levels. Furthermore, we studied the interaction of the signals of rods cones by stimulating the two sinusoidally with different temporal frequencies.

Publications

• ARVO Annual Meeting Abstract | June 2021: Combining temporal white noise stimulation and silent substitution technique: wnERGs driven by single photoreceptor types in LIAIS mice
  Anneka Joachimsthaler; Nina Stallwitz & Jan J. Kremers
  
• ARVO Annual Meeting Abstract | June 2022: A novel approach to analyze white noise ERGs in mice
  Nina Stallwitz; Anneka Joachimsthaler & Jan J. Kremers
  
• ARVO Annual Meeting Abstract | June 2022: How the use of dim red-light pre-recording affects ERG responses of mice with long-wavelength shifted opsin
  Anneka Joachimsthaler; Nina Stallwitz & Jan J. Kremers
  
• Luminance white noise electroretinograms (wnERGs) in mice. Frontiers in Neuroscience, 16.
  Stallwitz, Nina; Joachimsthaler, Anneka & Kremers, Jan
  
• Single opsin driven white noise ERGs in mice. Frontiers in Neuroscience, 17.
  Stallwitz, Nina; Joachimsthaler, Anneka & Kremers, Jan