Gap junctions and connexin hemichannels both contribute to the electrical properties of retinal pigment epithelium

Julia Fadjukov, Sophia Wienbar, Satu Hakanen, Vesa Aho, Maija Vihinen-Ranta, Teemu O. Ihalainen, Gregory W. Schwartz, Soile Nymark

Research output: Contribution to journalArticleScientificpeer-review


Gap junctions are intercellular channels that permit the transfer of ions and small molecules between adjacent cells. These cellular junctions are particularly dense in the retinal pigment epithelium (RPE), and their contribution to many retinal diseases has been recognized. While gap junctions have been implicated in several aspects of RPE physiology, their role in shaping the electrical properties of these cells has not been characterized in mammals. The role of gap junctions in the electrical properties of the RPE is particularly important considering the growing appreciation of RPE as excitable cells containing various voltage-gated channels. We used a whole-cell patch clamp to measure the electrical characteristics and connectivity between RPE cells, both in cultures derived from human embryonic stem cells and in the intact RPE monolayers from mouse eyes. We found that the pharmacological blockade of gap junctions eliminated electrical coupling between RPE cells, and that the blockade of gap junctions or Cx43 hemichannels significantly increased their input resistance. These results demonstrate that gap junctions function in the RPE not only as a means of molecular transport but also as a regulator of electrical excitability.

Original languageEnglish
Article numbere202112916
Number of pages17
JournalJournal of General Physiology
Issue number4
Publication statusPublished - 11 Mar 2022
Publication typeA1 Journal article-refereed

Publication forum classification

  • Publication forum level 2

ASJC Scopus subject areas

  • Physiology


Dive into the research topics of 'Gap junctions and connexin hemichannels both contribute to the electrical properties of retinal pigment epithelium'. Together they form a unique fingerprint.

Cite this