The Variational Tendency Of Related Neurotrophic Factors In The Disease Of Diabetic Keratopathy In Rats

Objective:To establish the diabetic keratopathy model in rats,and explore the variational tendency of related neurotrophic factors(including ciliary neurotrophic factor,nerve growth factor and insulin-like growth factor-1)in the cornea of diabetic keratopathy.The aim of this research is to explore the diabetic keratopathy's pathogenesis.Methods:The rats were randomly divided into a control group(n=18)and experimental group(n=18).The rats were further divided into three subgroups according to the time after the experimental procedures: 8-week subgroup(n =6),10-week subgroup(n =6),and 12-week subgroup(n = 6).In experimental group,rats were intraperitoneally injected using higf-dose streptozotocin to establish type 1 diabetes mellitus,while in the control group,rats were intraperitoneally injected using the same amount of citrate buffer solution.After building the model,we detect the variational tendency of blood glucose every two weeks.Using the corneal sensitivity detector to detect the the corneal sensitivity.The rats in the experimental group and the control group were put to death at 8 weeks,10 weeks and 12 weeks after modeling.Using haematoxylin-eosin staining to detect the tissue pathology changes of cornea.Otherwise,we detect the variational tendency of ciliary neurotrophic factor,nerve growth factor and insulin-like growth factor-1 in the tissue of diabetic keratopathy's cornea using q RT-PCR.Results: 1)The blood glucose in the experimental group increased significantly compared with the control group(P<0.05).The weight of diabetic rats did not see significant increase compared with before(P>0.05).2)The corneal sensitivity in the experimental group did not see significant changes in the time of 6 weeks compared with the control group(P>0.05).With the time goes by,corneal sensitivity in the experimental group decreased significantly in the time of 8 weeks compared with the control group(P<0.05).Otherwise,corneal sensitivity in the 8-week subgroup decreased significantly compared with the 6-week subgroup(P<0.05).Corneal sensitivity in the 12-week subgroup decreased significantly compared with the 10-week subgroup(P<0.05).3)Detecting the cornea through haematoxylin-eosin staining: In the control group,the epithelial cells were well arranged,the basement membrane was intact,and we did not see edema in the cornea.While in diabetic 8-week subgroup,we can see the gap outside the cells become larger,and cavitation in the cell becomes larger and edema of cornea.In the diabetic 10-week subgroup,the form of epithelial cells become abnormal,arranged in disorder and edema of cornea.In the diabetic 12-week subgroup,the epithelial cells become sparsely,significant edema of cornea and epithelial injury of cornea.4)q RT-PCR detection results finding that,the cntf in the experimental group decreased significantly compared with the control group(p<0.05),but increased in the time of corneal epithelium injury happened(p<0.05).The ngf in the experimental group(in the time of 8-weeks)did not see significant changes compared with the control group(p>0.05),while in the time of 10-weeks and 12-weeks decreased significantly compared with the control group(p<0.05).The igf-1 in the experimental group(in the time of 8-weeks)increased significantly compared with the control group(p>0.05),while in the time of 10-weeks and 12-weeks decreased compared with the control group(p<0.05).Conclusion: Related neurotrophic factors(CNTF,NGF,IGF-1)have an important role in the diabetic keratopathy.With the development of disease,the factors's expression becomes less and less.As a result,the cornea loses its nutrition and appears pathologic change.