Research on the Stability of a Rabbit Dry Eye Model Induced by Topical Application of the Preservative Benzalkonium Chloride

Dry eye is a common disease worldwide, and animal models are critical for the study of it. At present, there is no research about the stability of the extant animal models, which may have negative implications for previous dry eye studies. In this study, we observed the stability of a rabbit dry eye model induced by the topical benzalkonium chloride (BAC) and determined the valid time of this model.). Decreased levels of mucin-5 subtype AC (MUC5AC), along with histopathological and ultrastructural disorders of the cornea and conjunctiva could be observed in Group BAC-W4 and particularly in Group BAC-W5 until day 21.A stable rabbit dry eye model was induced by topical 0.1% BAC for 5 weeks, and after BAC removal, the signs of dry eye were sustained for 2 weeks (for the mixed type of dry eye) or for at least 3 weeks (for mucin-deficient dry eye)

Canine lacrimal and third eyelid superficial glands’ macroscopic and morphometric characteristics Aspectos macroscópicos e morfométricos das glândulas lacrimal e superficial da terceira pálpebra de cães (Canis familiares; LINNAEUS, 1758)

The lacrimal and third eyelid superficial glands produce the aqueous component of the preocular tear film. In this research, morphologic and morphometric assessments of the parenchyma and stroma of both lacrimal glands of healthy adult mongrel dogs were performed. Both lacrimal and third eyelid glands of fourteen dogs were collected, summing fifty-six samples. The macroscopic and morphometric data were statistically analyzed, according to the glandular type (lacrimal and third eyelid superficial glands) and sexual dimorphism (male or female). The lacrimal glands were significantly larger and longer than the superficial glands of the third eyelid. Expressive morphometric differences of interlobular duct, lymphocytic infiltration, interlobular vessels and secretory parenchyma between the two glandular types were encountered. The lacrimal glands from the male subjects were significantly larger than those from female ones, as well as the superficial glands of the third eyelid were thicker. The higher lymphocyte infiltration and poorer secretor parenchyma in female dogs may be one of the reasons for the higher incidence of keratoconjunctiviti sicca (KCS) in such canine population.<br>As glândulas lacrimal e superficial da terceira pálpebra atuam produzindo o componente aquoso do filme lacrimal. Nesta pesquisa, estudaram-se aspectos morfológicos e morfométricos do parênquima e do estroma de ambas as glândulas em cães mestiços, hígidos, adultos (machos ou fêmeas). As glândulas lacrimal e superficial da terceira pálpebra de 14 cães foram colhidas, totalizando 56 amostras. Foram estudadas, à estatística, as variáveis macroscópicas e morfométricas, comparando-as quanto ao tipo glandular (lacrimal e superficial da terceira pálpebra) e quanto ao dimorfismo sexual (macho e fêmea). Às glândulas lacrimais foram significativamente maiores comparativamente as superficiais da terceira pálpebra. Foram evidenciados diferenças morfométricas expressivas quanto aos vasos e ductos interlobulares, ducto interlobular, infiltração linfocitária e parênquima secretório entre os dois tipos glandulares. As glândulas lacrimais dos machos foram significativamente maiores comparativamente às fêmeas, assim como as glândulas superficiais da terceira pálpebra apresentaram-se mais espessas. A maior infiltração linfocitária e a menor proporção de parênquima secretor nas fêmeas poderá ser uma das razões para uma maior incidência de ceratoconjuntivite seca (CCS) em fêmeas na população canina