title: New insights into pathophysiological mechanisms regulating conventional aqueous humor outflow.
abstract: The aim of the article was to overview the pathophysiology of the conventional outflow pathway, trabecular meshwork, and intraocular pressure and to discuss the options of future glaucoma treatment directed to improvement in aqueous outflow. The literature search in the Medline, Embase, and Cochrane databases from April to May 2012 was performed; a total of 47 articles analyzed. The diminished conventional pathway may be altered by several pathophysiological mechanisms like TM obstruction caused by transforming growth factor-β2, clastic nondeformable cells, macrophages leaking from hypermature cataract, iris pigment, lens capsular fragments after YAG-laser posterior capsulotomy, proteins and their subfragments. It is known that trabecular meshwork contraction reduces outflow, and the actomyosin system is directly linked to this mechanism. New glaucoma drugs are still under investigation, but it is already proven that agents such as latranculin-B are effective in improving aqueous drainage. Selective Rho-associated coiled coilforming protein kinase inhibitors have been shown to cause a significant improvement in outflow facility and may become a new option for glaucoma treatment. Caldesmon negatively regulates actin-myosin interactions and thus increases outflow. Stem cells may replace missing or nonfunctional trabecular meshwork cells and hopefully will bring a new treatment solution. Pathophysiological mechanisms regulating conventional aqueous humor outflow are still not fully understood and require further investigations. Future treatment decisions should be directed to a specific mechanism regulating an elevation in intraocular pressure.
authors.affiliation: Department of Eye Diseases, Medical Academy, Lithuanian University of Health Sciences, Eivenių 2, 50028 Kaunas, Lithuania. daiva_paulaviciute@yahoo.com
authors.forename: Daiva
authors.initials: D
authors.lastname: Paulavičiūtė-Baikštienė
authors.forename: Rūta
authors.initials: R
authors.lastname: Baršauskaitė
authors.forename: Ingrida
authors.initials: I
authors.lastname: Janulevičienė
mesh_terms: D000367:Age Factors; D001082:Aqueous Humor / Q000378:metabolism*; D005901:Glaucoma / Q000188:drug therapy* / Q000503:physiopathology*; D006575:Heterocyclic Compounds, 3-Ring / Q000627:therapeutic use; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000627:therapeutic use; D014129:Trabecular Meshwork / Q000378:metabolism* / Q000503:physiopathology*
chemical_list: D006575:Heterocyclic Compounds, 3-Ring; D047428:Protein Kinase Inhibitors; C478429:latonduine B