Characterization of nitrergic neurons in the porcine and human ciliary nerves.
OBJECTIVE
To further characterize a subpopulation of choroidal ganglion cells associated with the ciliary nerves.


METHODS
Isolated long ciliary nerves of porcine and human eyes containing ciliary nerve-associated ganglion cells (CNGCs) were embedded in Epon for ultrastructural investigation, or wholemounts were stained with antibodies against nitric oxide synthase (NOS), vasoactive intestinal polypeptide (VIP), vesicular acetylcholine transporter, neuropeptide Y (NPY), tyrosine hydroxylase (TH), calcitonin gene-related peptide (CGRP), substance P (SP), and synaptophysin. In addition, wholemount preparations of the choroid and of the anterior segment were stained for reduced nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-D). Serial sections through choroid and anterior segment were stained with the prior antibodies listed.


RESULTS
In the porcine choroid only CNGCs were present. They stained for brain (b)NOS and VIP and were surrounded by SP and VIP-immunoreactive (IR) nerve terminals. The axonal processes of the CNGCs followed the ciliary nerves to the anterior eye segment, where they formed a nerve fiber plexus that terminated in the trabecular meshwork. None of the axons passed into the sparse NOS-IR nerve fiber plexus surrounding the choroidal vasculature. The CNGCs in the human choroid morphologically resembled those seen in the pig.


CONCLUSIONS
The CNGC proportion of choroidal ganglion cells is presumably involved in the intrinsic (peripheral) innervation of the aqueous outflow tissues and of the choroid.
May
C Albrecht
CA
Department of Anatomy II, University of Erlangen-Nürnberg, Universitaetsstrasse 19, 91054 Erlangen, Germany.
Fuchs
Anne V
AV
Scheib
Michael
M
Lütjen-Drecoll
Elke
E
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D002352:Carrier Proteins / Q000378:metabolism; D002924:Ciliary Body / Q000294:innervation* / Q000648:ultrastructure; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D017950:Ganglia, Sensory / Q000378:metabolism / Q000648:ultrastructure; D006801:Humans; D008297:Male; D026901:Membrane Transport Proteins; D008875:Middle Aged; D009252:NADPH Dehydrogenase / Q000378:metabolism; D009474:Neurons / Q000201:enzymology* / Q000648:ultrastructure; D009478:Neuropeptide Y / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052248:Nitric Oxide Synthase Type I; D013373:Substance P / Q000378:metabolism; D013552:Swine; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism; D050494:Vesicular Acetylcholine Transport Proteins; D033921:Vesicular Transport Proteins
D002352:Carrier Proteins; D026901:Membrane Transport Proteins; D009478:Neuropeptide Y; C493459:SLC18A3 protein, human; D050494:Vesicular Acetylcholine Transport Proteins; D033921:Vesicular Transport Proteins; D013373:Substance P; D014660:Vasoactive Intestinal Peptide; C496320:NOS1 protein, human; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; D014446:Tyrosine 3-Monooxygenase; D009252:NADPH Dehydrogenase; D015740:Calcitonin Gene-Related Peptide