Ca2+ is an obligatory intermediate in the excitation cascade of limulus photoreceptors

  • Shin J
  • Richard E
  • Lisman J
  • 20


    Mendeley users who have this article in their library.
  • 60


    Citations of this article.


We have investigated the role of Ca2+in the excitation of Limulus photoreceptors by intracellular injection of the Ca2+buffer, 5,5′-dibromo-BAPTA. Buffer with free Ca2+of 0.5 or 5 μM slowed the rising edge of the light response over 100-fold and greatly reduced both the transient and plateau phases of the light response, as expected if Ca2+elevation is necessary for all phases of excitation. Injection of buffers with free Ca2+of 5 or 45 μM, levels normally reached during light, evoked sustained inward current as expected if Ca2+is sufficient for excitation. The transduction cascade appears due to a single pathway that sequentially involves 1,4,5-trisphosphate inositol, Ca2+, and cyclic GMP. © 1993.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Get full text


  • Junghoon Shin

  • Edwin A. Richard

  • John E. Lisman

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free