March 2012
Volume 53, Issue 14
Free
ARVO Annual Meeting Abstract  |   March 2012
Changes In P2X Receptor Activity During Retinal Degeneration
Author Affiliations & Notes
  • Aleksandra Polosukhina
    UC Berkeley, Berkeley, California
  • Andy Noblet
    UC Berkeley, Berkeley, California
  • Ivan Tochitsky
    UC Berkeley, Berkeley, California
  • Richard H. Kramer
    UC Berkeley, Berkeley, California
  • Footnotes
    Commercial Relationships  Aleksandra Polosukhina, None; Andy Noblet, None; Ivan Tochitsky, None; Richard H. Kramer, None
  • Footnotes
    Support  NIH Grant EY018957; NIH Grant EY018241; Funds from Beckman Foundation for Macular Research
Investigative Ophthalmology & Visual Science March 2012, Vol.53, 6541. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Aleksandra Polosukhina, Andy Noblet, Ivan Tochitsky, Richard H. Kramer; Changes In P2X Receptor Activity During Retinal Degeneration. Invest. Ophthalmol. Vis. Sci. 2012;53(14):6541.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose: : P2X7, P2X4, and P2X2 receptors have been found to play vital role in inflammation, perception of pain, and apoptosis, thus possibly contributing to retinal ganglion cell death during retinal degeneration. The aim of this study was to assess the changes in activity of these receptors in retinal cells during the progression of retinal degeneration using a novel photosensitive reporter (QAQ).

Methods: : QAQ enters through open P2X receptors, and silences the affected cells in a light reversible manner. By recording the activity of RGC cells in different wavelengths of light we assessed the amount of intracellular QAQ, which serves as a cumulative reporter of the P2X receptor activity. To determine whether P2X receptors were expressed in the rd1 mouse retinas, we extracted the retinas and directly treated them with QAQ and 2' and 3'-O-(4-benzoylbenzoyl)-ATP (bzATP, a potent P2X receptor agonist). To assess the activity of the P2X receptors, the eyes from rd1 mice (6 and 3 month old) were injected with QAQ; the retinas were then extracted and placed on the multielectrode array (MEA).

Results: : We found that application of bzATP did not induce QAQ loading in 3 month old mice while a high amount of QAQ loading was observed in 6 month old mice after bzATP application. Thus, 6 month old mice showed a significant increase in firing rate in response to light (p < 0.001). Additionally, we found that in in-vivo experiments QAQ loading was only observed in 6 month old mice, showing a significant firing rate increase in response to light (p < 0.001).

Conclusions: : The in-vivo experiments suggest that P2X receptors become more active in the later stages of retinal degeneration, allowing large molecules like QAQ enter retinal cells. Additionally, the ex-vivo experiments with direct application of bzATP and QAQ suggest that P2X receptors are more active in older rd1 mice.

Keywords: retinal degenerations: cell biology • retina 
×
×

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.

×