Ultrastructure of Aplysia neurons having different degrees of light sensitivity

J. M. Krauhs, Michael Andresen, P. S. Baur, A. M. Brown

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The relationship between ultrastructure and photosensitivity of pigmented neurons of the abdominal ganglion of Aplysia californica was investigated using electron microscopy and electrophysiological methods. Four identified neurons of similar light microscopic appearance were examined; two are photoresponsive and two are not. Illumination hyperpolarizes both responsive neurons. One of them, R2, requires roughly 100 times greater light intensities than does the other, the ventral photoresponsive neuron (VPN), for similar responses. Two neurons lying adjacent to VPN and similar in appearance to VPN do no have measurable electrophysiological responses to even the highest light intensities. All four neurons contained lipochondria, pigmented organelles associated with the light response. Therefore the presence of these organelles is not the only requirement for light sensitivity in these neurons. Illumination appeared to increase the number of membranous lipochondria in both R2 and the ventral neurons, but only in R2 was this increase significant. Factors such as the concentration of lipochondria near the plasma membrane may affect quantitative aspects of the light response, but in the insensitive cells the lipochondria are apparently uncoupled from other factors required of the light response.

Original languageEnglish (US)
Pages (from-to)455-464
Number of pages10
JournalJournal of Neurobiology
Volume10
Issue number5
StatePublished - 1979
Externally publishedYes

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Aplysia
Photophobia
Neurons
Light
Lighting
Organelles
Ganglia
Electron Microscopy
Cell Membrane

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

Ultrastructure of Aplysia neurons having different degrees of light sensitivity. / Krauhs, J. M.; Andresen, Michael; Baur, P. S.; Brown, A. M.

In: Journal of Neurobiology, Vol. 10, No. 5, 1979, p. 455-464.

Research output: Contribution to journalArticle

Krauhs, J. M. ; Andresen, Michael ; Baur, P. S. ; Brown, A. M. / Ultrastructure of Aplysia neurons having different degrees of light sensitivity. In: Journal of Neurobiology. 1979 ; Vol. 10, No. 5. pp. 455-464.
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