The Expression Of Autonomic Nerve Markers On Trabecular Meshwork-schlemm's Canal

Glaucoma is a type of severe irreversible blindness disease characterized by optic nerve atrophy and visual field defect.Intraocular pressure(IOP)is considered to be the main controllable risk factor for glaucoma.The trabecular meshwork(TM)-Schlemm's canal(SC)is the main resistance point of the aqueous humor drainage channel,and it is also a key part that affects intraocular pressure fluctuations.Clinical studies have confirmed that there is a correlation between the opening and closing status of SC and the fluctuation of intraocular pressure: when the SC expands,the intraocular pressure decreases;when the SC collapses,the intraocular pressure increases,and the increased intraocular pressure is positive correlate with the degree of collapse of SC.Previous research by our research group found that the autonomic nerves may play a role in regulating the opening and closing state of SC.But whether the peripheral nerves anatomically project to the tissues around the SC or not is unexplored so far,and the role and mechanism of autonomic nerves are not clear.In this study,we intend to explore the role of autonomic nerves in the regulation of SC by Immunohistochemistry and immunofluorescence.CD31 was used to identify SC,after which we used protein gene product(PGP)9.5 as a marker to detect nerve fibers around SC.We then characterized the nerves by double staining for PGP9.5 and sympathetic nerve markers,such as tyrosine hydroxylase(TH)and dopamine beta-hydroxylase(D?H),or the parasympathetic marker vasoactive intestinal peptide(VIP),as well as sensory nerve marker calcitonin gene-related peptide(CGRP)and vesicular glutamate transporter 2(VGlu T2).By detecting the nerve fibers of TM and SC in the donated eyes,the types and characteristics of nerve distribution were clarified;and then comparing the nerve fibers of TM and SC between chronic IOP hypertension rat model and normal rats to investigating the role of autonomic nerves in SC regulation.Finally,we compare the nerve fibers located in the TM-SC tissues between the chronic angle-closure glaucoma eyes and the donated eyes to confirm whether the changes of markers in patients were the same as in rats.