Functional role of spines in the retinal horizontal cell network.
- 1 January 1989
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 86 (1), 387-391
- https://doi.org/10.1073/pnas.86.1.387
Abstract
Compartmental models derived from serial electron-microscopic reconstructions of horizontal cell processes entering cone pedicles and rod spherules are used to show that these processes have the morphological and electrical characteristics of dendritic spines. Properties of these spines are incorporated into a distributed model of the horizontal cell network. Expressions relating the magnitude of conductance changes applied at the spine heads to hyperpolarization of cells within the network are derived. Model analyses show that spine properties play a critical role in determining network responses. Specifically, increasing spine stem resistance increases the network input resistance and space constant, hyperpolarizes the resting potential, decreases response to full-field light stimuli, and increases response to small light spots. Increasing spine-stem resistance also decouples potential at the spine head from potential at the cell body. This result suggests that the location of feedback neurotransmitter release sites (e.g., at the spine heads versus the cell body) may have a profound influence on properties of horizontal cell inhibition of cone response. Because of these important functional consequences, structurally realistic models of the horizontal cell network must incorporate spine properties.This publication has 19 references indexed in Scilit:
- Morphological and physiological studies of rod-driven horizontal cells with special reference to the question of whether they have axons and axon terminalsJournal of Comparative Neurology, 1987
- Axons connecting somata and axon terminals of luminosity‐type horizontal cells in the turtle retina: Receptive field studies and intracellular injections of HRPJournal of Comparative Neurology, 1983
- A theoretical analysis of electrical properties of spinesProceedings of the Royal Society of London. B. Biological Sciences, 1983
- Gap junctions among the perikarya, dendrites, and axon terminals of the luminosity‐type horizontal cell of the turtle retinaJournal of Comparative Neurology, 1983
- Light-dependent plasticity of the morphology of horizontal cell terminals in cone pedicles of fish retinasJournal of Neurocytology, 1980
- Goldfish Retina: A Correlate Between Cone Activity and Morphology of the Horizontal Cell in Clone PediculesScience, 1979
- Horizontal cells of the turtle retina. II. Analysis of interconnections between photoreceptor cells and horizontal cells by light microscopyJournal of Comparative Neurology, 1978
- Horizontal cell axons and axon terminals in goldfish retinaJournal of Comparative Neurology, 1975
- Color‐specific interconnections of cones and horizontal cells in the retina of the goldfishJournal of Comparative Neurology, 1975
- The Fine Structure of the Horizontal Cells in Some Vertebrate RetinaeCold Spring Harbor Symposia on Quantitative Biology, 1965