| Study on Activity Changes of Na, K-ATPase and carbonic anhydrase ofCiliary Body after Traumatic Anterior Proliferative Vitreoretinopathy and Retinal Structural and Functional Changesafter Chronic HypotonyObjective: To study the changes of activity of two important enzymes related to the productivity of aqueous humor, namely Na, K-ATPase and carbonic anhydrase, and to probe more into the mechanism of traumatic anterior proliferative vitreoretinopathy inducing chronic hypotony. To observe the changes of retinal function and structure after traumatic chronic hypotony, and to discuss the possible mechanism of lesions.Method: At first the rabbit model of chronic hypotony due to traumatic anterior proliferative vitreoretinopathy was made. In treated group, lens nucleus and some cortices were removed through a corneal limbus incision, and iris and ciliary body was cut radiatively at 11 and 5 o' clock to let the blood flow out naturly from the blood vessel in the root of iris. Capsule was broken into pieces by discission needle. Blood, capsule pieces and the remanent lens cortices were blended with vitreous near the ciliary bosy. In contrasted group, only the lens was removed by ECCE. At the 2nd week, 4th week, 8thweek, 16th week after trauma, IOP was measured and electroretinogram (ERG) was examined. Then eyeballs were removed and part of ciliary body and retina were taken for ordinary pathological section and HE staining, part of ciliary body was used for mensuration of Na, K-ATPase' s activity and histochemistry examination of carbonic anhydrase, part of retina at the 16th week after trauma was send for electron microscopy exam.Result: (1)IOP: IOP of treated group decreased gradually after trauma,while IOP of contrasted group decreased at the beginning, becamestable afterward. There is significant difference between two groups.(2) Pathological changes of ciliary body: At the 2nd week aftertrauma, in treated group, the ciliary process is swelling and thereis fibrinoid exudation on the surface of ciliary process, while thestructure of the pigmental and nonpigmental epithelia is normal. Incontrasted group, the ciliary process is also swelling and there isless fibrinoid exudation on the surface of ciliary process. Thestructure of the pigmental and nonpigmental epithelia is normal. Atthe 4th week after trauma, in treated group, there is still a littleciliary body swelling, and proliferated fibriform matter can be seenon the surface of ciliary process, but structure of the pigmentaland nonpigmental epithelia is nearly normal. In contrasted group,there is no ciliary body swelling, and there is little proliferatedfibriform matter on the surface of ciliary process. At the 8th and16th week after trauma, in treated group, there is nearly no ciliarybody swelling, and much proliferated fibriform matter can be seen on the surface of ciliary process, and parts of the pigmental and nonpigmenta epithelia have disordered structure, even some parts are atrophy or disappeared. In contrasted group, there are little proliferated fibriform matter on the surface of ciliary process and ciliary epithelia are normal. The lesions of ciliary epithelia by traumatic anterior proliferative vitreoretinopathy are not equal in every part. Some parts got heavy lesions and the structure of epithelia is disordered or atrophy, even disaooeared, while some parts are nearly normal. (3) Changes of activity of Na, K-ATPase and carbonic anhydrase: Activity of Na, K-ATPase decreased gradually in treated group but there is no remarkable decrease in contrasted group. There is significant difference between two groups. In treated group the colour of some ciliary epithelia were thick brownish black after histochemistry examination of carbonic anhydrase performed, indicating the activity of carbonic anhydrase is nearly normal. These parts are nearly normal epithelia when contrasted to HE stained section. But the destroyed epithelia were mild yellowish brown, indicating the activity o... |
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