Properties of multivesicular release from mouse rod photoreceptors support transmission of single-photon responses.

Journal Article (Journal Article)

Vision under starlight requires rod photoreceptors to transduce and transmit single-photon responses to the visual system. Small single-photon voltage changes must therefore cause detectable reductions in glutamate release. We found that rods achieve this by employing mechanisms that enhance release regularity and its sensitivity to small voltage changes. At the resting membrane potential in darkness, mouse rods exhibit coordinated and regularly timed multivesicular release events, each consisting of ~17 vesicles and occurring two to three times more regularly than predicted by Poisson statistics. Hyperpolarizing rods to mimic the voltage change produced by a single photon abruptly reduced the probability of multivesicular release nearly to zero with a rebound increase at stimulus offset. Simulations of these release dynamics indicate that this regularly timed, multivesicular release promotes transmission of single-photon responses to post-synaptic rod-bipolar cells. Furthermore, the mechanism is efficient, requiring lower overall release rates than uniquantal release governed by Poisson statistics.

Full Text

Duke Authors

Cited Authors

  • Hays, CL; Sladek, AL; Field, GD; Thoreson, WB

Published Date

  • March 26, 2021

Published In

Volume / Issue

  • 10 /

PubMed ID

  • 33769285

Pubmed Central ID

  • PMC8032395

Electronic International Standard Serial Number (EISSN)

  • 2050-084X

Digital Object Identifier (DOI)

  • 10.7554/eLife.67446

Language

  • eng

Conference Location

  • England