July 2019
Volume 60, Issue 9
Free
ARVO Annual Meeting Abstract  |   July 2019
Distribution of inter-endothelial junction and vascular mural cells may account for iridal volume change during pupil reflexion
Author Affiliations & Notes
  • Hongfang Yang
    Ophthalmology Department, Fudan University, Shanghai, China
  • Footnotes
    Commercial Relationships   Hongfang Yang, None
  • Footnotes
    Support  None
Investigative Ophthalmology & Visual Science July 2019, Vol.60, 6164. doi:https://doi.org/
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Hongfang Yang; Distribution of inter-endothelial junction and vascular mural cells may account for iridal volume change during pupil reflexion. Invest. Ophthalmol. Vis. Sci. 2019;60(9):6164. doi: https://doi.org/.

      Download citation file:


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

      ×
  • Supplements
Abstract

Purpose : The volume change of iris during pupil reflexion has been highlighted to be related to primary angle closure glaucoma recently. Though the mechanism of iridal volume change is unclear while exudation in the anterior chamber is commonly observed around pupil in clinic. We hypothesize that high permeability exists in iridal pupil region, and both inter-endothelial junctions and mural cells contribute to the blood-aqueous barrier.

Methods : Twenty-one freshly enucleated porcine eyes were divided into two groups. 12 eyes were applied for permeability test and perfused through temporal long posterior ciliary artery (LPCA) at 200µm/min with FITC-albumin 0min (2eyes), 2min (5eyes) and 8min (5eyes); the other 9 eyes were used for perfusion labelling with VE-cadherin, claudin-5 and αSMA. Iris was cryosectioned for confocal microscopy followed by further HE and Van Gieson staining for eyes of permeability test. Iris sectors were flat-mounted for all experimented eyes. Images were taken under the same laser intensity, and signal intensities were compared among eyes as well as iris vascular segments by three observers.

Results : Porcine iris vasculature is permeable to albumin since 2min after perfusion though lower and slower than ciliary process. Iris vascular permeability is different among regions. Pupillary region, especially at the superficial and deep capillary network, showed stronger FITC signal than ciliary region. Correspondingly, these areas of iris pupillary region were occupied by microvasculature which showed weak, uneven and discontinuous claudin-5 labelling. Meanwhile, vessels in these areas were only partially covered by scarce αSMA positive vascular mural cells.

Conclusions : Iris pupillary region is more permeable to albumin than iris ciliary region, which may due to the distribution pattern of inter-endothelial tight junction proteins and contractive vascular mural cells. Further quantitative study will be needed to confirm whether the volume change of iris is remarkably obvious in this region than others.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.

 

The weak and uneven inter-endothelial juntions (VE-cadherin and Claudin-5) and scarce mural cells covering only a part of the microvascular surface correspond well to the iris regional difference on vascular permeability. It may imply the regional differnce on iris volume change.

The weak and uneven inter-endothelial juntions (VE-cadherin and Claudin-5) and scarce mural cells covering only a part of the microvascular surface correspond well to the iris regional difference on vascular permeability. It may imply the regional differnce on iris volume change.

×
×

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.

×