实验性视网膜脱离Na^+-K^+-转运ATP酶活性及RPE超微结构改变

THE CHANGES OF ACTIVITY OF Na + K + ATPase AND ULTRASTRUCTURES OF RPE IN EXPERIMENTAL RETINAL DETACHMENT

目的：探讨实验性视网膜脱离（ｒｅｔｉｎａｌｄｅｔａｃｈｍｅｎｔ，ＲＤ）后视网膜色素上皮（ｒｅｔｉｎａｌｐｉｇｍｅｎｔｅｐｉｔｈｅｌｉｕｍ，ＲＰＥ）对视网膜下液（ｓｕｂｒｅｔｉｎａｌｆｌｕｉｄ，ＳＲＦ）的输导功能。方法：将制作成功的实验性单眼ＲＤ２８只家兔随机分为４组，每组７只，每只兔的另眼作为对照。分别取ＲＤ部位的ＲＰＥ－脉络膜组织和对照眼相应部位的组织匀浆，再测定ＡＴＰ水解产物无机磷含量，以判断ＡＴＰ酶活性；并作实验和对照眼的两种组织相应部位的ＲＰＥ电镜观察。结果：实验眼Ｎａ＋－Ｋ＋－转运ＡＴＰ酶活性为（２．１６±１．２６）μｍｏｌ／（ｍｇｈ），对照眼为（４．８４±１．５９）μｍｏｌ／（ｍｇｈ），二者差异显著（ｔ＝５．５２，Ｐ＜０．０１）；酶活性降低程度随病程延长而减轻（Ｐ＜０．０５）。电镜观察实验眼ＲＤ后第２至４周有自脉络膜向视网膜方向的吞饮泡，且随病程延长而增多。结论：ＲＤ发生后ＲＰＥ的外向输导功能增强，随病程进展，此功能减弱而内向输导功能产生。

OBJECTIVE:To investigate the transporting function of subretinal fluid in retinal pigment epithelium(RPE) of experimental retinal detachment(RD).METHODS:Twenty seven pigmented rabbits with one eye as retinal detachment model and the other eye as control were divided into 4 groups,ie.7 rabbits in each group at random.The Na + K + ATPase activity in RPE choroidal tissue at the detached region in both experimental and control eyes was determined at the lst,2nd,3rd and 4th week after retinal detachment,and also the ultrastructure of the RPE choroidal tissues observed.RESULTS:The activity of Na + K + ATPase of experimental eyes[(2.16±1.26)μmol/(m·h)]was significantly lower than that of the controls[(4.84±1.59)μmol/(m·h)].The degree of decreasing activity was relieving along with increasing of the course of RD.The inward pinocytosis in RPE cells under electron microscope was found from the 2nd week samples afterwards and becoming obvious along with increasing of the disease course.CONCLUSIONS:The outward transporting function of RPE was increased after RD,it became decreased along with increasing of the course of RD and the inward transporting function then developed.