IBRO WORKSHOP

29-30 January, 2020 - Szeged, Hungary

 
 

Abstract details

PROX1 IMMUNREACTIVITY AND ELECTRICAL SYNAPSE DENSITY IN THE MAMMALIAN RETINA

01/29/2020

Katalin Fusz13,Cecília Horváth13, Péter Kóbor13, Tamás Kovács-Öller23, Béla Völgyi23, Edina Szabó-Meleg234, Péter Buzás13, Ildikó Telkes13

1 Institute of Physiology, Medical School, University of Pécs

2 Szentágothai Research Centre, University of Pécs

3 Centre for Neuroscience, University of Pécs,

4 Department of Biophysics, Medical School, University of Pécs

Introduction: Recently, we have identified two patterns of gap junction distribution in the cat retina: one that is eccentricity dependent and is linked to AII amacrine cells, and an eccentricity independent pattern. Objective: Here, we were interested if similar patterns are found in the rat retina.Methods: As a test, we mapped the expression patterns of the homeodomain protein Prox1 and the major neuronal gap junction protein, connexin-36 across the retinal layers and at various retinal locations using fluorescence immunohistochemistry in the rat retina. We analysed the laminar distribution and areal density of the labelled structures. We used the density of Prox1-positive horizontal cells as a measure of eccentricity. Results: We found Prox1 immunoreactivity in the cell bodies of subpopulations of horizontal, bipolar, amacrine and ganglion cells. Connexin-36 plaques were found in the inner plexiform layer of all retinal areas, with the highest density in the ON-sublamina. Here, plaque density correlated significantly with horizontal cell density (r = 0.44, p = 0.05). Conclusions: We found Prox1 immunoreactivity in all neurone types except photoreceptors of the rat retina. The data are compatible with an eccentricity dependent decrease in electrical coupling in the inner plexiform layer.