51. Intraocular pressure elevation precedes a phagocytosis decline in a model of pigmentary glaucoma
- Author
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Priyal Shah, Ralitsa T. Loewen, Nils A. Loewen, Chao Wang, Susannah Waxman, and Yalong Dang
- Subjects
0301 basic medicine ,Intraocular pressure ,medicine.medical_specialty ,Pigment dispersion glaucoma ,Open angle glaucoma ,genetic structures ,Phagocytosis ,Glaucoma ,Ocular hypertension ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Fluorescent microspheres ,0302 clinical medicine ,Ophthalmology ,medicine ,General Pharmacology, Toxicology and Pharmaceutics ,aqueous outflow ,General Immunology and Microbiology ,business.industry ,trabecular meshwork ,phagocytosis ,Articles ,General Medicine ,medicine.disease ,eye diseases ,medicine.anatomical_structure ,030104 developmental biology ,030221 ophthalmology & optometry ,Trabecular meshwork ,sense organs ,business ,Ex vivo ,Research Article ,intraocular pressure - Abstract
Background: Outflow regulation and phagocytosis are key functions of the trabecular meshwork (TM), but it is not clear how the two are related in secondary open angle glaucomas characterized by an increased particle load. We hypothesized that diminished TM phagocytosis is not the primary cause of early ocular hypertension and recreated pigment dispersion in a porcine ex vivo model. Methods: Sixteen porcine anterior chamber cultures received a continuous infusion of pigment granules (Pg), while 16 additional anterior chambers served as controls (C). Pressure transducers recorded the intraocular pressure (IOP). The phagocytic capacity of the trabecular meshwork was determined by fluorescent microspheres. Results: The baseline IOPs in Pg and C were similar (P=0.82). A significant IOP elevation occurred in Pg at 48, 120, and 180 hours (all PP=0.001 compared to C). This reduction did not result in an additional IOP increase at 120 or 180 hours compared to the first IOP elevation at 48 hours (P>0.05). Conclusions: In this porcine model of pigmentary glaucoma, an IOP elevation occurs much earlier than when phagocytosis fails, suggesting that two separate mechanisms might be at work.
- Published
- 2018