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)
PURPOSE:To study the retinal pathologic changes and pathogenesis of relinhis pigmenlosa(RP). METHODS:The relina from a patient with autosomal dominant RP was examined by light and electron microscopy. RESULTS:Degeneration and structure disturbance almost involved in every layer of retina and were accompanied hy regional differenecs:Posterior region was more than periphery one in severity. Degeneration of retinal pigment epithelium(RPE)closely eorrelaled to that of the phmoreceplor. The uhraslrneture of the retina showed extensive and severe degeneration in the photoreeeptors ,particularly ill omer segments and mitoehondrlas. Lipofusein gramdes were accumuhtted in the cytoplagm. CONClUSIONS:These changes suggested that self-energizing system and self engulfing system of the photoreceptols were disfunctloned. (Chin J Ocul Fundus Dis,1997,13: 24-26)
rough the ultramicroscopic observation on muscle and microcirculation, Group A,where a largeamount of DXM combined with heporin was given svstematically and locally into the femoral artery of the severed limb before replantation, and in Group B only heporin was given, and Group C and D ascontrol.The results showed that if the hormone and heparin were administred in large dosage, it wasadvantageous to reduce the tissues from reperfusion injury during delayed replantation.
Objective To probe the change of the structure and function of the small bowel by injection of different drugs (verapamil, energy compounds or normal saline) via the superior mesenteric artery (SMA) injections.Methods The model of the small intestine ischemia/reperfusion (I/R) injury was made in grey rabbits. Free calcium concentration in mitochondria of the small intestine was determined, and the ultrastructural change was also observed by electron microscopy at the very time of occlusion, 60 minutes after occlusion and 30 minutes after reperfusion. Results The free calcium concentration in mitochondria was more declined in verapamil group (2.976±0.410 nmol/mg.prot) than in N.S. group (4.234±0.542 nmol/mg.prot), P<0.01, at 60 minutes after occlusion. At 30 minutes after reperfusion, free calcium concentration in mitochondria was more decreased in energy compunds group (2.401±0.323 nmol/mg.prot) and verapamil group (3.847±0.610 nmol/mg.prot) than in the N.S. group (5.981±1.031 nmol/mg.prot). Conclusion Verapamil and energy compouds have protective effects on the functions and ultrastructures of the I/R of small intestine.
In order to investigate the effect of nerve compression on neurons, the commonly used model of chronic nerve compression was produced in 48 SD rats. The rats were sacrificed in 1, 2, 3, 4, 5 and 6 months after compression, respectively. The number of neuron and ultrashruchure of alpha-motor neurons and ganglion cells of the corresponding spinal segment were examined. The results showed as following: After the sciatic nerve were crushed, the number of neuron and ultrastructure of alpha-motor neurons and ganglion cells might undergo ultrastructural changes, and even the death might occur. These changes might be aggravated as the time of crushing was prolonged and the compression force was increased. It was concluded that for nerve compression, decompression should be done as early as possible in order to avoid or minimize the ultructural changes of the neuron.
Objective:To observe the histochemical changes of retinal photochemical damage in rats. Methods:The changes of retinal ultrastructure were observed.The concentration of malondaldehyde(MDA) was tested and the activity the histochemical change of cytochrome oxidase (CCO) and (Mg ++ -ATPasw) were evaluated on the retnal photochemical damage in SD rats. Results:At the 6th hour after light exposure,the swelling appwared at the nuclei of photoreceptor,the mitochondria of inner segment.The apical microvilli of RPE disappeared and lysosomes increased in RPE.On the 6th day after light exposure,the changes became more obvious.While on the 14th day after light expose the nuclei of photoreceptors and the inner segments renewed but the arrangement of the disk was lose;and the microvilli appeared of the disk was lose;and the microvilli appeared at the tip of RPE.The Activity of CCO and Mg ++ -ATPase decreased and MDA increased in retina at the 6th hour and on the 6th day and they recovered on the 14th day after light exposure. Conclusion:Lipd peroxidation that broke the cell membrane system of photoreceptor which induced changes of the cell ultrastru cture abd the activity of enzyme might relate to pathogenesis in retinal photochemical damage. (Chin J Ocul Fundus Dis,1998,14:38-40)
Objective To study the ultrastructure of macular puck er (MP) from the patients with rhegmatogenous retinal detachment (RRD) and the mechanism associated with its development. Methods Twenty specimens of MP surgically removed by vitrectomy from 13 patients were dissected into two layers in each of them.The ultrastructure of two layers,i,e,near the vitreous and near the retina,was studied with electron microscopy. Results Seven sections of the near vitreous ones appeared prodominant collagen deposits and a few of epithelial like cells,and pigment particles might be present in the cytoplasm.While cells with foot processes were found in 13 membrane sections near the retina and increasing number of various types of cells rich in collagen around were observed including fibroblast like cells and glial cells. Conclusion The findings suggest that the MP after surgery of retinal detachment may possess a characteristic lamination,and posterior hyaloid cortex was involved in the developmetn of MP. The adhesion between posterior hyaloid cortex and macular area might be a key factor for forming MP. (Chin J Ocul Fundus Dis, 2001,17:52-54)