Development of synaptic arrays in the inner plexiform layer of neonatal mouse retina

J Comp Neurol. 1979 Sep 15;187(2):359-72. doi: 10.1002/cne.901870207.


Retinas from mice of the C57BL/6 strain were sampled at frequent intervals from birth to postnatal day 33 to determine the numerical density of conventional and ribbon synapses within the inner plexiform layer (IPL) as a function of time. Synaptic arrays of the IPL were formed in three phases. During Phase I, from day 3 to day 10, conventional synapses were produced at a mean rate of 0.44 synapses/1,000 micrometer3/hour, but no ribbons were seen. During Phase II, from day 11 to day 15, ribbons formed at a rate of 0.38 ribbons/1,000 micrometer3/hour and conventional synapses were produced at a rate of 1.15 synapses/1,000 micrometer3/hour. Phase III began at day 15, the approximate time of eye opening in these animals, and was characterized by a sharp reduction in the rate of production of both ribbons and conventional synapses. During this phase ribbons achieved a final mean density of 113 ribbons/1,000 micrometer3 and conventionals achieved a final mean density of 250 synapses/1,000 micrometer3. Serial appeared in Phase II but remained at low densities.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Goldfish / anatomy & histology
  • Mice
  • Mice, Inbred C57BL
  • Neurons / cytology
  • Retina / cytology
  • Retina / growth & development*
  • Retina / ultrastructure
  • Species Specificity
  • Synapses / physiology
  • Synapses / ultrastructure
  • Xenopus / anatomy & histology