title: Effect of mitomycin C on the tensile properties of the upper lacrimal canaliculi in a rabbit model.
abstract: The upper lacrimal canaliculus consists of a tubular structure, and the tensile properties which in lacrimal tissues might contribute to structural integrity and tear drainage. We evaluated the characteristics of the tensile properties of the upper lacrimal canaliculi and the clinical implications of using a mitomycin C (MMC)-treated rabbit model. Mitomycin C (0.04%) was applied to the punctum of rabbits for 5 min, and the upper lacrimal tissues including the punctum were excised and attached to a forced transducer to record the tensile properties in a resting state 1 month later. The recording showed continuing decrement of basal tension with time in the lacrimal tissues treated with MMC in contrast with normal controls which maintained initial tension throughout the experiment. The rabbits were then randomly divided into the following 3 groups: vertical punctal incision with the MMC application group; vertical punctal incision with a balanced salt solution application group; and a balanced salt solution application only group. Four weeks after surgery, the puncta of rabbits treated with an incision and MMC application were more dilated clinically and showed less elasticity as compared with the other groups. Histological staining revealed that MMC treatment combined with incision decreased the amount of collagen and elastin fibers in the canaliculi. These results suggest that lacrimal canaliculi of rabbits have rheological basal tension and elasticity, which can be decreased by the use of MMC treatment.
authors: Department of Ophthalmology, College of Medicine, Chung-Ang University Hospital, #224-1, Heukseok-Dong, Dongjak-Gu, Seoul 156-755, Republic of Korea. lk1246@gmail.com
authors: Jeong Kyu
authors: JK
authors: Lee
authors: Moo Yeol
authors: MY
authors: Lee
authors: Mi Kyung
authors: MK
authors: Kim
authors: Nam Ju
authors: NJ
authors: Moon
mesh_terms: D000477:Alkylating Agents / Q000494:pharmacology*; D000818:Animals; D003094:Collagen / Q000378:metabolism; D004548:Elasticity / Q000502:physiology*; D004549:Elastin / Q000378:metabolism; D005143:Eyelids / Q000378:metabolism / Q000601:surgery; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000473:pathology; D007124:Immunoenzyme Techniques; D007765:Lacrimal Apparatus / Q000502:physiology*; D008297:Male; D016685:Mitomycin / Q000494:pharmacology*; D011817:Rabbits; D009418:S100 Proteins / Q000378:metabolism; D013718:Tensile Strength / Q000187:drug effects*
chemical_list: D000477:Alkylating Agents; D009418:S100 Proteins; D016685:Mitomycin; D003094:Collagen; D004549:Elastin