Functional role of spines in the retinal horizontal cell network

R. L. Winslow, Robert F Miller, T. E. Ogden

Research output: Contribution to journalArticlepeer-review

8 Scopus citations

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.

Original languageEnglish (US)
Pages (from-to)387-391
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Volume86
Issue number1
DOIs
StatePublished - 1989

Fingerprint Dive into the research topics of 'Functional role of spines in the retinal horizontal cell network'. Together they form a unique fingerprint.

Cite this