Objective To observe the morphological changes of dendrite and soma in retinal ganglion cells (RGCs) which subsisted in early diabetic rats. Methods The RGCs of 3-months-course diabetic rats and coeval normal rats were marked by gene gun techniques. To collect RGCs photographs by Leica microscope with Z axis and CCD camera；to observe the changes of diameter, variance of structural features in dendritic field and somata after classification which according to the size and morphology. Thy-1 antibody marks on the retinal RGCs, taking a photograph under fluorescent microscope, counting the changes of retinal RGCs density in early diabetic rat. Results In three-month diabetic rats,the density of retinal RGCs was decreased obviously. Morphological changes of RGCs in the dendritic fields were observed with gene gun technique. There was no severe variation in all kinds of the bole of cell dendrite, in which some only showed crispation partially and sparseness also twisting in the dendritic ramus. The mean diameter of dendritic field and soma in class A of diabetic rats was (401plusmn;86) mu;m, the mean diameter of dendritic field in control group was (315plusmn;72) mu;m,compared with each other, there is statistically significant differences (t=21.249，Plt;0.001); the mean diameter of soma in class A of diabetic rats was (24plusmn;6) mu;m, the mean diameter of soma in control group was (22plusmn;5) mu;m, compared with each other, there is no statistically significant differences (t=0.927，Pgt;0.05); the mean diameter of dendritic field and soma in class B of diabetic rats were (170plusmn;36)、(14plusmn;2) mu;m respectively, in control group were (165plusmn;36)、(16plusmn;2) mu;m, the mean diameter of dendritic field and soma in class C of diabetic group were(265plusmn;78)、(17plusmn;5) mu;m respectively, in control group were (251plusmn;57)、(17plusmn;4) mu;m , compared with each other, there are on statistically significant differences(t=1.357，0.798，0.835，1.104，Pgt;0.05). Conclusions In short-term diabetes, the survived RGCs show good plasticity in adult diabetic rats, especially in class A. The changes of dendrites were more sensitive than the soma, which could be the leading index of the morphologic changes of RGCs in the early stage. The good plasticity showed by the RGCs and the time window from changing in dendrite to cell death provide us many evidences not only for the research but also for the nerve protection in clinic. (Chin J Ocul Fundus Dis,2008,24:249-254)
ObjectiveTo investigate the effects of form deprivation on the morphology of different types of RGC in mice.MethodsSixty B6.Cg-Tg (Thy1-YFP) HJrs/J transgenic mice were randomly assigned to form-deprived group (n=28) and control group (n=32). The right eyes of mice in the form-deprived group were covered by an occluder for 2 weeks as experimental eyes. The right eyes of mice in the control group were taken as control eyes. Before and 2 weeks after form deprivation, the refraction and ocular biometrics were measured; RGC were stained with Bra3a antibody and counted; the morphology of RGC was reconstructed with Neuroexplore software after immunohistochemical staining. The data was compared among experimental eyes, fellow eyes and control eyes by one-way analysis of variance.ResultsTwo weeks after form deprivation, the axial myopia was observed in the experimental eyes (refraction: F=15.009, P＜0.001; vitreous chamber depth: F=3.360, P=0047; ocluar axial length: F=5.011, P=0013). The number of RGC in central retina of the experimental eyes was decreased compared with the fellow eyes and the control eyes (F=4.769, P=0.035). The reconstructed RGC were classified into 4 types according to their dendritic morphology. Form deprivation affected all 4 types of RGC but in a different way. Among them, 3 types of RGC were likely contribute to form vision perception. Form deprivation increased the dendrite branches in these types of ganglion cells. However, form deprivation decreasd dendrite segment numbers in both eyes and the intersection and length insholl analyse type 4 ganglion cells which were morphologically identified as ipRGC.ConclusionForm deprivation distinguishingly affects the morphology of different types of RGC, indicating that form vision and non-form vision play different role in myopia development.