Substance P in rat corneal and iridal nerves: an ultrastructural immunohistochemical study.
The distribution of substance P (SP) within the nerve fibers of the rat cornea and iris was studied using electron microscopic immunohistochemistry. Numerous SP-immunoreactive fibers were found throughout the corneal and iridal stroma. The most intense staining was found within varicosities containing numerous vesicles. Similar SP-immunoreactive varicosities were found in fibers in close proximity to the iris sphincter and dilator muscles. On account of previous ultrastructural work the SP-containing fibers and varicosities must be assumed to be of trigeminal origin. Additionally, the distribution of SP and calcitonin gene-related peptide (CGRP) in corneal and iridal fibers of rats is similar, suggesting that CGRP and SP are colocalized and may be coreleased from the same varicosities.
Beckers
H J
HJ
Department of Morphology, The Netherlands Ophthalmic Research Institute, Amsterdam.
Klooster
J
J
Vrensen
G F
GF
Lamers
W P
WP
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism; D003315:Cornea / Q000294:innervation* / Q000648:ultrastructure; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D007498:Iris / Q000294:innervation* / Q000648:ultrastructure; D008297:Male; D016253:Microscopy, Immunoelectron; D009412:Nerve Fibers / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats; D017208:Rats, Wistar; D013373:Substance P / Q000378:metabolism*
D013373:Substance P; D015740:Calcitonin Gene-Related Peptide