gms | German Medical Science

102. Jahrestagung der DOG

Deutsche Ophthalmologische Gesellschaft e. V.

23. bis 26.09.2004, Berlin

Intrinsic choroidal neurons (ICN) in human: non-nitrergic subpopulation

Meeting Abstract

  • corresponding author F. Schrödl - Anatomy I, Erlangen
  • A. Jünemann - Ophthalmology, Erlangen
  • A. Bergua - Ophthalmology, Erlangen
  • A. De Laet - Physiology and Histology, Antwerp/B
  • J. P. Timmermans - Histology, Antwerp/B
  • M. J. Tassignon - Ophthalmology, Edegem/B
  • A. Brehmer - Anatomy I, Erlangen
  • W. L. Neuhuber - Anatomy I, Erlangen

Evidenzbasierte Medizin - Anspruch und Wirklichkeit. 102. Jahrestagung der Deutschen Ophthalmologischen Gesellschaft. Berlin, 23.-26.09.2004. Düsseldorf, Köln: German Medical Science; 2004. Doc04dogP 124

The electronic version of this article is the complete one and can be found online at:

Published: September 22, 2004

© 2004 Schrödl et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.




Nitrergic intrinsic choroidal neurons (ICN) innervate vascular and stromal non-vascular smooth muscle cells, hence influencing choroidal blood flow and choroidal thickness. Studies of ICN topography with different markers (NADPH-d: Bergua et al., 2003; neurofilament-staining: Trivino et al., 2002) revealed different ICN densities in temporal versus nasal quadrants. This suggested the existence of a significant non-nitrergic subpopulation. Therefore, the aim of ths study was to quantify subpopulations of ICN with different neuronal markers, as well as to search for an overall marker of ICN.


11 choroidal wholemounts from donor eyes (53-84 years of age; 1-16 hrs p.m.) were processed for immunohistochemical single and double stainings for the following markers: NADPH-d, cocktail of neurofilament 160/200kD (NF), protein-gene product 9.5 (PGP9.5), and neuronal nitric oxide synthase (nNOS), respectively. For documentation, light-, fluorescence- and confocal laserscanning microscopy were used.


The combination of NADPH-d and PGP 9.5 revealed that about 6% of the total population of ICN were positive for PGP 9.5 only, without preferential topography. Double labelling with NF and nNOS revealed, that about 20% of the total population of ICN were positive for NF only and about 6% for nNOS only, respectively, again without topographical preference.


Our results show, that there is a hitherto unrecognized NF+ non-nitrergic subpopulation of ICN, the chemical nature and targets of which have to be further elucidated. Differences in ICN topography published up to now may indicate age or desease related alterations within the choroid.