title: Effects of gelatin hydrogel containing chymase inhibitor on scarring in a canine filtration surgery model.
abstract: OBJECTIVE
  To investigate the effects of gelatin hydrogel (GH) containing a chymase inhibitor (CI) on intraocular pressure (IOP) and conjunctival scarring in a canine model of glaucoma surgery.
  
  
  METHODS
  Glaucoma surgery models were made in beagles. As the first experiment, GH was implanted. IOP was measured for 4 weeks, followed by histologic evaluation. As the second experiment, GH containing a CI or GH alone was implanted. IOP and bleb features were evaluated for 12 weeks. The densities of proliferative cell nuclear antigen (PCNA)-positive cells, fibroblasts, and mast cells were quantified. The mRNA levels of transforming growth factor-β (TGF-β) and chymase were determined by real-time PCR.
  
  
  RESULTS
  In the first experiment, IOP was significantly lower in the eyes treated with GH than that in the control eyes. The conjunctival area normalized by the scleral area was reduced in the treated eyes. In the second experiment, IOP reduction was maintained for 12 weeks in the eyes treated with GH containing a CI, but not in the eyes treated with GH alone. In addition, the bleb score was larger, whereas the adhesion score and densities of PCNA-positive cells, fibroblasts, mast cells, and chymase-positive cells were lower in the eyes treated with GH containing a CI. The mRNA levels of TGF-β and chymase were significantly decreased in the eyes treated with GH containing a CI.
  
  
  CONCLUSIONS
  Implanting GH alone maintained IOP reduction, whereas GH containing a CI enhanced the IOP-reducing effect by suppressing cell proliferation. This drug delivery system might be useful for maintaining filtering blebs for a longer duration after glaucoma surgery.
authors.affiliation: Department of Ophthalmology, Osaka Medical College, Takatsuki, Osaka, Japan.
authors.forename: Shota
authors.initials: S
authors.lastname: Kojima
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Shinji
authors.initials: S
authors.lastname: Takai
authors.forename: Denan
authors.initials: D
authors.lastname: Jin
authors.forename: Maho
authors.initials: M
authors.lastname: Shibata
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Oku
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Tabata
authors.forename: Tsunehiko
authors.initials: T
authors.lastname: Ikeda
mesh_terms: D000818:Animals; D053818:Chymases / Q000037:antagonists & inhibitors* / Q000235:genetics; D002921:Cicatrix / Q000517:prevention & control; D003229:Conjunctival Diseases / Q000473:pathology / Q000517:prevention & control*; D004195:Disease Models, Animal; D004285:Dogs; D004338:Drug Combinations; D016503:Drug Delivery Systems; D005347:Fibroblasts / Q000378:metabolism / Q000473:pathology; D005355:Fibrosis / Q000517:prevention & control; D005780:Gelatin / Q000008:administration & dosage; D005901:Glaucoma / Q000601:surgery*; D020100:Hydrogels / Q000008:administration & dosage; D007124:Immunoenzyme Techniques; D007429:Intraocular Pressure / Q000502:physiology; D008407:Mast Cells / Q000378:metabolism / Q000473:pathology; D009842:Oligopeptides / Q000008:administration & dosage*; D011099:Polyglutamic Acid / Q000008:administration & dosage; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D014065:Tonometry, Ocular; D014130:Trabeculectomy; D016212:Transforming Growth Factor beta / Q000235:genetics
chemical_list: D004338:Drug Combinations; D020100:Hydrogels; D009842:Oligopeptides; D018809:Proliferating Cell Nuclear Antigen; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; C101913:gelatin-polyglutamic acid glue; C102024:succinyl-valyl-prolyl-phenylalanyl-diphenylphosphonate; D011099:Polyglutamic Acid; D005780:Gelatin; C509226:CMA1 protein, human; D053818:Chymases