May 2008
Volume 49, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2008
Effect of Intravitreal Nitric Oxide on the Rat Electroretinogram
Author Affiliations & Notes
  • M. Sato
    Laboratory of Neurobiology, Department of Biology, Graduate School of Sciences, Toho University, Funabashi, Japan
  • T. Ohtsuka
    Laboratory of Neurobiology, Department of Biology, Graduate School of Sciences, Toho University, Funabashi, Japan
  • Footnotes
    Commercial Relationships  M. Sato, None; T. Ohtsuka, None.
  • Footnotes
    Support  None.
Investigative Ophthalmology & Visual Science May 2008, Vol.49, 2206. doi:https://doi.org/
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      M. Sato, T. Ohtsuka; Effect of Intravitreal Nitric Oxide on the Rat Electroretinogram. Invest. Ophthalmol. Vis. Sci. 2008;49(13):2206. doi: https://doi.org/.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose: : The intraretinal concentration of nitric oxide (NO) is increased by light adaptation; the intravitreal NO concentration in the rat eye is ~0.5 µM during nighttime, but ~1 µM during daytime (Hoshi et al., 2003). To investigate the role of this NO increase in visual information processing, we recorded the electroretinogram (ERG) after injecting the NO donor, S-nitroso-N-acetylpenicillamine (SNAP), into the vitreous body of the rat eye.

Methods: : Sprague Dawley rats, 8 - 10 wks old, were used. The dark-adapted rat was anesthetized by 20% urethane i.p., with 0.4% procaine-HCl on the cornea and atropine sulfate for dilation. 2 µL of SNAP (#346-070771, Dojin), 5 mM in PBS, was injected into the vitreous body by a microsyringe. Since the half-time for release of NO from SNAP is 5 hr, the estimated intravitreal NO concentration was ~3 µM for the first hr. 2 µL of 1M monosodium glutamate (Glu) was injected alone or prior to SNAP for isolation of ERG a-wave. ERG to a green LED light, 70 µW/cm2 at the corneal surface, was recorded from the left eye; the right eye served as reference.

Results: : 10 min after SNAP injection, the ERG a-wave decreased by ~40% and the b-wave by ~30%. This decrease lasted >4 hrs. The amplitudes of oscillatory potentials also decreased by ~50%. Glu decreased the b-wave gradually until only the a-wave remained after 30 min; the b-wave was suppressed completely for >90 min and then recovered gradually. SNAP injection 30 min after Glu had no effect on the ‘cone a-wave’, but reduced the ‘rod a-wave’ amplitude by ~30%; the suppressed ‘rod a-wave’ was gradually replaced by the recovering b-wave after 90 min.

Conclusions: : Our in situ experiment showed that NO selectively suppressed the rod a-wave, but not the cone a-wave. This suggests that the release of NO in the retina may mediate the suppression of rod activity during light-adaptation, thus expanding the dynamic range of cone input to second-order neurons.

Keywords: nitric oxide • electroretinography: non-clinical • retina: distal (photoreceptors, horizontal cells, bipolar cells) 
×
×

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.

×