The Effect Of Optical Defocus To Refractive Status Of Guinea Juvenile Pigs

ObjectiveTo observe the effect of optical defocus to refractive status of guinea pigs,then,to explore the minimum degree of concave lens induced myopia and the minimum degree of convex lens induced hypermetropic eye in guinea pigs which provides experimental basis to prevention and treatment of myopia.Methods75 3-4-week-old guinea pigs were randomly divided into 10 groups,1-10 group for the experimental group,in which the length of axis oculi,diopter were measured before and after wearing two weeks,wearing separately different degrees of lens-induced in the right eye,and the left eye was as control eye.Then compare the distribution of tyrosine hydroxylase(TH)in the retina after immunohistochemical staining.ResultsThe diopter of+7D,+4D,-4D,-7D groups compared with the control eyes were statistically significant differences(P＜0.05),while+3D,+2D,+1D,-1D,-2D,-3D groups were not(P＞0.05).The changes of-4D,-7D groups were obvious before and after wearing in the length of axis oculi,while the other groups were not.The TH protein can express in retina of each group,which were mainly distributed in amacrine cell layer,the expression of TH in experimental eyes of-7D,-4D group was less than other groups'experimental eyes and all the control eyes,the difference has statistical significance.There was no significant difference between-7D and-4D.Conclusions 1.The growth and development of Guinea pig eye can be affected by lens which depended on setting up animal models of ametropia.2.The minimum degree of concave lens induced myopia was lens-4D,and eminimum degree of convex lens induced hypermetropic eyes+4 D.3.TH protein mainly distributed in the retinal inner nuclear layer,and TH protein in retina of guinea pigs of myopia was less than in the control eye,while there was no significant difference between hypermetropic eye and the control eyes.