| Myopia or nearsightedness is a commonly and frequently encountered disease in ophthalmology. It is not clear about its pathogenesis, but form deprivation (FM) theory has played an important role in the study of myopia pathogenesis. FM, which means using multiple methods to effect the normal formation in the retina can result in abnormal growth of ocular globe, showing longer axial length and leading to myopia.There were some foreign reports about relationship of MMP, TIMP and FDM, but the mechanism is not clear yet. In my experiment, myopia is characterized by excessive axial lengthening of the ocular globe and morphological changes. Using HE staining, SABC staining, SDS-PAGE and WB to study the express changes of scleral morphology, collagen types, MMP-2 and TIMP-2 in FDM. We hope study and understand the pathogenesis of FDM.1. The express changes of scleral collagen types in the deprived eyes of FDMMaterials and methods: Forty healthy male hailan chickens were selected afterborn 2 days. All the right eyes underwent form deprivation with translucent goggles, and the left eyes were used as the control. After deprived for 1, 3, 5, 7 and 14 days, the refractive state of the deprived eyes were characterized by means of streak retinoscopy (without cycloplegia), then the eye globes were removed and its axial length were measured by sliding gage. Routine fixation, dehydration, diaphanous, paraffin and embedding were done. Sum paraffin sections were taken. We used routine hematoxylin-eosin (HE) staining and observed the morphological changes of deprived sclera under light microscopy. Streptaridin-biotin-peroxidase complex (SABC) immunohistochemistry method was used to study the express changes of collagen types.Results: (1). Form deprivation leads to myopia refractive abnormality. After deprived for 1, 3, 5, 7 and 14 days, the average dipoter of the deprived eyes were +1.937?.079 D, -2.78?.27 D, -9.17?.22 D, -14.275?.609 D, -20.56?.51 D, and the axial length of the deprived eyes were +8.265?.15 mm, +8.995?.069 mm, +9.33?.05 mm, +9.6?.106 mm, +9.78?.44 mm. Significant differences were detected in axial length and diopter between deprived and control eyes (P<0.01). (2) HE staining shows that the deprived posterior cartilaginous sclera was thicker and the fibrous sclera was thinner than control sclera. The number of cells in the deprived cartilaginous sclera was more than control sclera. (3) Immunohistrochemistry staining shows that there were collagen type I mainly in deprived eyes and collagen type III in control eyes.Conclusions: Form deprivation leads to myopia refractive abnormality, and thelonger the eyes were deprived, the more severe the myopia refractive state was. Morphological changes of sclera were associated with an increased thickness of cartilaginous and a decreased thickness of fibrous within the posterior sclera. The express changes of scleral collagen types were related with an increased amount of collagen type I and a decreased amount of collagen type III.2. The express changes of MMP-2 and TIMP-2 in deprived and recovering eyesMaterials and methods: 80 healthy male hailan chickens were selected. The right eyes were deprived after born 2 days and the left eyes were control. Two groups were divided at random. One was experimental group and the other was recovering group. The deprived eyes were discovered after being deprived 2 weeks. The refractive state was characterized by means of streak retinoscopy. Then killed the chickens and removed the eye globes. Using a surgical trephine, 8mm diameter tissue buttons of posterior sclera were excised. The attached ocular tissues were separated. The five tissue-buttons form each group were homogenized together in 0.01M Tris ?HC1, ph 8.0. Insoluble material was removed from the homogenized material by centrifugation at 10,000 rpm for 20 minutes. The supernatant was used for measurement. The recovering group was discovered after 2 weeks and feed normally for another 1 week. The specimens were made by the same method. The supern...
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