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Updated: Aug 8, 2026
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Simultaneous Whole-cell Recordings from Photoreceptors and Second-order Neurons in an Amphibian Retinal Slice Preparation
Published on: June 1, 2013
Sustained feedback effects of L-horizontal cells on turtle cones
Summary
Peripheral stimulation in turtle cones causes sustained electrical changes, revealing feedback from L-horizontal cells. These effects, linked to increased calcium conductance, are crucial for understanding retinal processing.
Area of Science:
- Neuroscience
- Vision Science
- Cellular Physiology
Background:
- Turtle cones exhibit complex electrical responses to peripheral stimulation.
- Previous studies focused on transient feedback mechanisms in retinal cells.
Purpose of the Study:
- To investigate sustained feedback effects of L-horizontal cells on turtle cones.
- To characterize the ionic mechanisms underlying sustained retinal responses.
Main Methods:
- Electrophysiological recordings from turtle cones.
- Peripheral stimulation with controlled light intensity and duration.
- Pharmacological manipulation using Co2+, Sr2+, and Ba2+.
Main Results:
- Prolonged peripheral illumination induced sustained depolarizations and oscillations in cones.
- These sustained effects were blocked by hyperpolarization and L-horizontal cell depolarization.
- Increased membrane Ca2+ conductance was associated with sustained peripheral stimulation responses.
Conclusions:
- L-horizontal cell feedback onto cones is both transient and sustained.
- Sustained feedback involves modulation of cone membrane excitability and calcium influx.
- These findings elucidate complex neural circuits in the vertebrate retina.
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