title: Twenty-four-Hour Measurement of Intraocular Pressure in Guinea Pigs (Cavia porcellus).
abstract: The objective of this study was to measure intraocular pressure (IOP) in intact, healthy guinea pigs (15 male, 15 female) every 2 h for a 24-h period. First, IOP was measured by using rebound tonometry (RBT). After a 1-min rest period, 0.5% proparacaine ophthalmic solution, a topical anesthetic, was applied to both eyes; 4 min after anesthetic instillation, IOP was measured by using applanation tonometry (APT). The IOP was lower during the light period (0700 to 1900) than during the dark phase (2000 to 0600). The lowest IOP by both RBT and APT (3.68 and 13.37 mm Hg, respectively) occurred at 0700, whereas maximal IOP occurred at 2300 for RBT (8.12 mm Hg) but at 2100 for APT (20.62 mm Hg). No significant differences in IOP between the left and right eyes or between RBT and APT were noted. In addition, daily variations in the IOP of guinea pigs seem to be independent of sex and body weight. The results of this study may be beneficial in the diagnosis and observation of glaucoma in guinea pigs.
authors.affiliation: Department of Clinical Sciences. Faculty of Specialized Veterinary Sciences, Science and Research Branch.
authors.forename: Maneli
authors.initials: M
authors.lastname: Ansari-Mood
authors.affiliation: Department of Clinical Sciences. College of Veterinary Medicine, Karaj Branch, Islamic Azad University, Alborz, Iran;, Email: Mehdi_13r@hotmail.com.
authors.forename: Seyed
authors.initials: S
authors.lastname: Mehdi-Rajaei
authors.affiliation: Department of Clinical Sciences. Faculty of Specialized Veterinary Sciences, Science and Research Branch.
authors.forename: Reza
authors.initials: R
authors.lastname: Sadjadi
authors.affiliation: Department of Clinical Sciences. College of Veterinary Medicine, Karaj Branch, Islamic Azad University, Alborz, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Selk-Ghaffari
authors.affiliation: Department of Veterinary Medicine, Madingley Road, Cambridge, UK CB3 0ES.
authors.forename: David L
authors.initials: DL
authors.lastname: Williams
mesh_terms: D000779:Anesthetics, Local; D000818:Animals; D001835:Body Weight; D005260:Female; D006168:Guinea Pigs; D007429:Intraocular Pressure; D008027:Light; D008297:Male; D008991:Monitoring, Physiologic; D012146:Rest; D014065:Tonometry, Ocular / Q000379:methods / Q000662:veterinary*
chemical_list: D000779:Anesthetics, Local
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