Cellular and Molecular Neurobiology

, Volume 4, Issue 2, pp 125–142 | Cite as

The electric organ ofDiscopyge tschudii: Its innervated face and the biology of acetylcholinesterase

  • Bernardita Méndez
  • Jorge Garrido
  • Mafalda Maldonado
  • Fabián M. Jaksic
  • Nibaldo C. Inestrosa


  1. 1.

    An ultrastructural, histochemical, and biochemical study of the electric organ of the South American Torpedinid ray,Discopyge tschudii, was carried out.

  2. 2.

    Fine structural cytochemical localization of acetylcholinesterase (AChE) indicated that most of the esterase was associated with the basal lamina. Electron microscopy indicated no marked differences in the electrocyte ultrastructure betweenDiscopyge andTorpedo californica.

  3. 3.

    Discopyge electric organ possessed three molecular forms, two asymmetric forms (16 S and 13 S) and one globular hydrophobic form (6.5 S). The asymmetric 16 S AChE form was solubilized by heparin, a sulfated glycosaminoglycan, suggesting that heparin-like macromolecules are involved in the binding of the enzyme to the basal lamina.

  4. 4.

    Our results show that cell-free translated AChE peptides, synthesized usingDiscopyge electric organ poly (A+) RNA, correspond to a main band of 62,000 daltons which probably represents the catalytic subunit of the asymmetric AChE.


Key words

16 S AChE synaptic basal lamina heparan sulfate proteoglycans cell-free synthesis of AChE electric organ acetylcholinesterase Discopyge tschudii 


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Copyright information

© Plenum Publishing Corporation 1984

Authors and Affiliations

  • Bernardita Méndez
    • 1
  • Jorge Garrido
    • 2
  • Mafalda Maldonado
    • 1
  • Fabián M. Jaksic
    • 3
  • Nibaldo C. Inestrosa
    • 1
  1. 1.Laboratory of Neurophysiology, Faculty of Biological SciencesCatholic University of ChileSantiagoChile
  2. 2.Laboratory of Histology, Faculty of Biological SciencesCatholic University of ChileSantiagoChile
  3. 3.Laboratory of Ecology, Faculty of Biological SciencesCatholic University of ChileSantiagoChile

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