Objective To investigate effects of neural retina on development of the structure of outer blood retinal barrier in embryogenesis. Methods The retinal neural epithelium (RNE) and pigment epithelium (RPE) layers of 150, 120 and 90 embryonic chicken eyes incubated for 7,10, and 14 days were peeled off. RNE was used to prepare the culture medium with different conditions (7drcSF3, 10drcSF3, 14drcSF3). RPE cells of 7- and 14-incubated chicken embryos were cultured on laminin-coated transwell filter. The SF3, 7drcSF3, 10drcSF3 , 14drcSF3 medium were used respectively in the apical chamber and SF2 was used in basolateral chamber. After the formation of monolayer, the transepithelial electrical resistance of the RPE was detected. After the fixation of RPE cells, the condition of the tight junction among the cells was observed by immunohis tochemistry and transmission electron microscopy. Results For the RPE cells of 7-and 14-day incubated embryonic eyes, the difference of TER in various medium of SF3/SF2, 7drcSF3/SF2, 10drcSF3/SF2, 14drcSF3/SF2 was statistically significant (P＜0.01). The polarity of RPE cells was induced and the netlike tight junctional strands was urged in the retina-conditioned medium. Conclusion The neural retina may actively promote the formation of the structure of outer blood retinal barrier. (Chin J Ocul Fundus Dis，2004，20：237-240)
PURPOSES:To investigate the time of neuronie apoptosis in the retinas of Imman fetuses,and its relations with neuronie proliferation and differentiation, METHODS:The retinas of 27 human fetuses from 8th to 38th week of R,~til- ization age and 3 adults were studied by TdT-mediated dUTP nick end labelling(TUNEL) method. RESULTS:Tbe nuctei of labeled apoptotic cells were charaeterised by nuclear marginization,ehromatln condensation and cleseent shape,and some apoptotie bodies were visible in the specimens. The apoptosis of neuroepithelium of fetal rclina took place during 8th to 18th week, Apoptosis of ganglion cells were observed from 1256 to 18th week. The apoptos[s of pholorec, plors were formd from 14th to 2Ist week ,while thai of bipolar neurones and M~ller cells were found from ldth to 28th week. No apoptosb of ocstones were observed in the retinas after 28th week of fertilization age and within the retinas of adults. CONCLUSION:The proliferating cells of neuroepithelium and Ihe neurones which just differetiated from fetal retina might partly undergo apoptosis. The time of apoptosls of differentiated neurones was consistent with the time of the synapses formation between neurones and their targel cells. （Chin J Ocul Fundus Dis,1997,13:67 -69 ）