Two-month-old male albino Swiss mice, Crl:CD1 (ICR), were purchased from Charles River (Barcelona, Spain). All experimental procedures were carried out in accordance with the Association for Research in Vision and Ophthalmology and the European Union Guidelines for the Use of Animals in Research and were approved by the Ethical and Animal Studies Committee of the University of Murcia (Spain).
Animals subjected to surgery: For anaesthesia, a mixture of xylazine (10 mg/kg body weight, Rompun; Bayer, Kiel, Germany) and ketamine (60 mg/kg body weight, Ketolar; Pfizer, Alcobendas, Madrid, Spain) was administered intraperitoneally (IP). After surgery, an ointment containing tobramycin (Tobrex; Alcon S.A., Barcelona, Spain) was applied to the cornea to prevent its desiccation. After surgery, mice were given oral analgesia (Buprex, Buprenorphine 0.3 mg/mL; Schering-Plough, Madrid, Spain) at 0.8 mg/kg (prepared in strawberry-flavored gelatine) the day of the surgery and up to a maximum of 3 days after the surgery.
All animals were killed with an IP overdose of pentobarbital (Dolethal, Vetoquinol; Especialidades Veterinarias, S.A., Alcobendas, Madrid, Spain).