June 2023
Volume 64, Issue 8
Open Access
ARVO Annual Meeting Abstract  |   June 2023
Kv11.1 potassium channels modulate the light response of retinal ON-bipolar cells
Author Affiliations & Notes
  • Catherine Morgans
    Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, United States
  • Tammie Haley
    Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, United States
  • Gaoying Ren
    Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, United States
  • Hope Shi
    Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, United States
  • Ryan Hecht
    Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, United States
  • R Lane Brown
    Washington State University, Pullman, Washington, United States
  • Robert Duvoisin
    Chemical Physiology & Biochemistry, Oregon Health & Science University, Portland, Oregon, United States
  • Footnotes
    Commercial Relationships   Catherine Morgans None; Tammie Haley None; Gaoying Ren None; Hope Shi None; Ryan Hecht None; R Brown None; Robert Duvoisin None
  • Footnotes
    Support  NIH Grant R01EY029985, NIH grant P30EY010572
Investigative Ophthalmology & Visual Science June 2023, Vol.64, 1928. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Catherine Morgans, Tammie Haley, Gaoying Ren, Hope Shi, Ryan Hecht, R Lane Brown, Robert Duvoisin; Kv11.1 potassium channels modulate the light response of retinal ON-bipolar cells. Invest. Ophthalmol. Vis. Sci. 2023;64(8):1928.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose : We investigated the expression and function of Kv11.1 potassium channels (gene name Kcnh2; ether-a-gogo related gene; erg1) in mouse retina. Kv11.1 is best known for its role in the repolarization of the cardiac action potential, and mutations in Kv11.1 are a major cause of long QT syndrome. Kv11.1 is also expressed in neurons where it regulates membrane excitability and firing frequency adaptation.

Methods : Kv11.1 transcripts were localized in mouse retinal sections by RNAscope. Kv11.1 expression in mouse retina was confirmed by western blotting, and its distribution in the retina determined by immunofluorescence confocal microscopy. Kv11.1 currents were demonstrated by measuring the effect of selective Kv11.1 blockers in patch-clamp recordings of rod bipolar cells in mouse retinal slices. The effect of Kv11.1 on the electroretinogram (ERG) was measured by comparing recordings from wildtype mice and conditional knockout mice (cKO) lacking Kv11.1 in ON-bipolar cells. The cKO mice were generated by crossing Kcnh2fl/fl mice with a mGluR6-Cre line.

Results : Retinal single cell transcriptomes indicate expression of the Kcnh2 gene, encodiong the Kv11.1 potassium channel, in bipolar cells. RNAscope coupled with PKCα immunofluorescence localized Kcnh2 mRNA to rod bipolar cells. Kv11.1 and PKCα double-labeling of dissociated retinal neurons demonstrated Kv11.1 immunofluorescence in rod bipolar cells. In retina sections, Kv11.1 co-localized with TRPM1 and GPR179 in ON-bipolar cells. Whole cell patch-clamp recordings from rod bipolar cells revealed voltage-gated potassium currents that were reduced by selective inhibitors of Kv11.1; tail currents typical of Kv11.1 were blocked to a greater extent. A conditional knockout mouse line was generated lacking Kv11.1 in ON-bipolar cells (cKO). ERG recordings showed an increase in the duration of the b-wave, as well as slower recovery of the scotopic b-wave following light exposure in the cKO mice compared to wildtype.

Conclusions : Our results suggest that Kv11.1 in ON-bipolar cells accelerates the termination of the retinal light response and and plays a role in dark adaptation.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.

×
×

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.

×