title: Effect of topical olopatadine and epinastine in the botulinum toxin B-induced mouse model of dry eye.
abstract: OBJECTIVE
  The aim of this study was to compare the effect of topical olopatadine, epinastine, and lubricant eye drops on dry eye ocular surface disease in the botulinum toxin B (BTX-B)-induced mouse model of keratoconjunctivitis sicca.
  
  
  METHODS
  CBA/J mice were randomized into 3 experimental groups of 10 animals each. All mice received a transconjunctival injection of 0.05 mL of 20-mU BTX-B solutions into the left lacrimal gland. Three (3) days after intralacrimal gland injections, each group received treatment with twice-daily topical lubricant as a control, 0.1% olopatadine, or 0.05% epinastine eye drops. To monitor the progression of dry eye tear production, an ocular surface fluorescein staining score was evaluated in each of the 3 experimental groups.
  
  
  RESULTS
  Three (3) days after the intralacrimal gland injection of BTX-B, aqueous tear production was significantly decreased (1.95+/-0.64 mm), compared to baseline level (2.69+/-0.66 mm; P<0.001). Similarly, there was a statistically significant increase in the proportion of mice with a corneal staining score of 2 or greater at 3 days postinjection, compared to the preinjection value (P<0.001). There were no statistically significant differences in aqueous tear production between the 3 different medication groups at all time points. Aqueous tear production in neither the olopatadine nor the epinastine-challenged groups was further decreased compared to the lubricant-treated group. Difference in the proportion of mice with a low- and high corneal staining score between the control and study groups did not reach statistical significance throughout the 4-week experimental period. In addition, changes in corneal fluorescein staining of the olopatadine group versus the epinastine group did not show a statistically significant difference.
  
  
  CONCLUSIONS
  Topical olopatadine and epinastine do not cause significantly additional damage to the compromised ocular surface secondary to dry eye after continuous 4-week, twice-daily application. Topical olopatadine and epinastine appear to have comparable effects on aqueous tear-production and corneal-surface changes in this mouse model.
authors.affiliation: Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD 21286-9278, USA.
authors.forename: Kaevalin
authors.initials: K
authors.lastname: Lekhanont
authors.forename: Choul Yong
authors.initials: CY
authors.lastname: Park
authors.forename: Juan Castro
authors.initials: JC
authors.lastname: Combs
authors.forename: Olan
authors.initials: O
authors.lastname: Suwan-Apichon
authors.forename: Ram
authors.initials: R
authors.lastname: Rangsin
authors.forename: Roy S
authors.initials: RS
authors.lastname: Chuck
mesh_terms: D000287:Administration, Topical; D000818:Animals; D001905:Botulinum Toxins / Q000633:toxicity; D019274:Botulinum Toxins, Type A; D003984:Dibenzazepines / Q000627:therapeutic use*; D003990:Dibenzoxepins / Q000627:therapeutic use*; D004195:Disease Models, Animal; D005260:Female; D006634:Histamine H1 Antagonists / Q000627:therapeutic use*; D007093:Imidazoles / Q000627:therapeutic use*; D007638:Keratoconjunctivitis Sicca / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D051379:Mice; D008808:Mice, Inbred CBA; D000069605:Olopatadine Hydrochloride; D013666:Tears / Q000378:metabolism
chemical_list: D003984:Dibenzazepines; D003990:Dibenzoxepins; D006634:Histamine H1 Antagonists; D007093:Imidazoles; C096323:rimabotulinumtoxinB; D000069605:Olopatadine Hydrochloride; D001905:Botulinum Toxins; D019274:Botulinum Toxins, Type A; C053090:epinastine