Differential distribution of neuronal markers and neuropeptides in the human lacrimal gland.
BACKGROUND
The present study was undertaken in an attempt to broaden the spectrum of known neuronal markers and neuropeptides in the main lacrimal gland of the human by light-microscopic immunohistochemistry.


METHODS
Using antisera against the neuronal markers protein gene product (PGP) and S-100 protein (S-100), the distribution of nerve fibers in the human main lacrimal gland was studied. Vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP), neuropeptide Y (NPY) and tyrosine hydroxylase (TH) were identified by their specific antisera.


RESULTS
The nerve fibers are distributed throughout the interstice between the glandular tubules. Associations were also found between nerve fibers and both the interlobular ductal system and blood vessels (mainly arterioles). Within the glandular lobules isolated groups of secretory cells stained positive for S-100 protein. Nerve fibers situated in the glandular interstice between the tubules showed predominantly positive immunoreactions for the neuropeptide VIP, while only very few fibers stained positive for CGRP, NPY and the catecholamine marker TH. Nerve fibers associated with interlobular blood vessels were mainly CGRP and NPY positive and stained only very rarely for VIP. The epithelia of interlobular ducts and excretory ducts were associated with CGRP-immunoreactive nerve fibers.


CONCLUSIONS
The neuropeptides identified in the lacrimal gland indicate the complexity with which a variety of biologic signals regulate and modulate the lacrimal gland.
Seifert
P
P
Alfried Krupp Laboratory, University Eye Hospital, Bonn, Germany.
Stuppi
S
S
Spitznas
M
M
Weihe
E
E
D000818:Animals; D015415:Biomarkers; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007765:Lacrimal Apparatus / Q000033:anatomy & histology / Q000378:metabolism*; D008297:Male; D009474:Neurons / Q000378:metabolism*; D009478:Neuropeptide Y / Q000378:metabolism; D009479:Neuropeptides / Q000378:metabolism*; D051381:Rats; D009418:S100 Proteins / Q000378:metabolism; D014018:Tissue Distribution; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism
D015415:Biomarkers; D009478:Neuropeptide Y; D009479:Neuropeptides; D009418:S100 Proteins; D014660:Vasoactive Intestinal Peptide; D014446:Tyrosine 3-Monooxygenase; D015740:Calcitonin Gene-Related Peptide