May 2008
Volume 49, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2008
Modulation by Calcium and Chloride of cAMP-Induced Short-Circuit Current Increase in Isolated Porcine Ciliary Processes
Author Affiliations & Notes
  • R. Wu
    Eye Center of the 2nd Affil/Opthalmology, Medical College of Zhejiang University, Hangzhou, China
  • Y. Ni
    Eye Center of the 2nd Affil/Opthalmology, Medical College of Zhejiang University, Hangzhou, China
  • I. Haefliger
    Laboratory of Ocular Physiology and Pharmacology, University Eye Clinic Basel, Basel, Switzerland
  • Footnotes
    Commercial Relationships  R. Wu, None; Y. Ni, None; I. Haefliger, None.
  • Footnotes
    Support  Swiss National Science Foundation (32-61495.00),National Natural Science Foundation of China (30400489)
Investigative Ophthalmology & Visual Science May 2008, Vol.49, 348. doi:https://doi.org/
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      R. Wu, Y. Ni, I. Haefliger; Modulation by Calcium and Chloride of cAMP-Induced Short-Circuit Current Increase in Isolated Porcine Ciliary Processes. Invest. Ophthalmol. Vis. Sci. 2008;49(13):348. doi: https://doi.org/.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: : To investigate how calcium and chloride modulate short-circuit current (Isc) increase induced by 8-bromo-cAMP (cAMP) in isolated porcine ciliary processes.

Methods: : In an Ussing-type chamber, peak Isc dose-response curves to the cAMP analogue 8-bromo-cAMP (0.01 µM - 30 µM) were constructed in isolated porcine ciliary processess. The effect of calcium channel blockers/stimulaters or calcium/chloride concentration in the bath solution on the Isc increase induced by cAMP analogue was assessed.

Results: : Only when applied on the non-pigmented epithelium side (NPE), 8-bromo-cAMP (0.01 - 30 µM) increased Isc (10 µM: 19.67 ± 2.44 µA/cm2). Isc increase was moderately inhibited by mibefradil (30 µM; P < 0.01), nimodipine (30 µM; P < 0.05), or a 0.5 mM calcium solution (P < 0.05), and almost abolished (P < 0.001) by a 0 mM calcium solution (with 2 mM EGTA) applied on the NPE. Isc increase was moderately enhanced by a 5 mM calcium solution (P < 0.01) or Bay K8644 (10 µM; P < 0.05) applied on the NPE. Isc increase was strongly inhibited by a 49.0 mM (P < 0.001) and 0 mM (P < 0.001) chloride solution applied on the pigmented epithelium side (PE). Inhibition by 0 mM chloride solution (PE) of Isc increase was not significantly affected by 0.5, 2.5, or 5 mM calcium solultion (NPE). Inhibition by 0 mM calcium (with 2 mM EGTA) solution (NPE) of Isc increase was not significantly affected by 0, 49.0, or 127.7 mM calcium solultion (PE).

Conclusions: : cAMP-induced Isc increase appears to involve an extracellular influx of calcium on the NPE side and the presence of chloride on the PE side in pig ciliary processes. Furthermore, the absence of chloride and calcium on the PE and NPE side, respectively, appears to be limiting factors in this processes.

Keywords: aqueous • calcium • ciliary processes 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×