Purpose To investigate retinoic acid (RA) induced apoptosis in retinal pigment epithelial (RPE) cells. Methods 10-5、10-6、10-7 mol/L were added to cultured PRE cells.Aridine orange fluorescence and TdT-mediated dUTP nick end labelling(TUNEL) techniques were used to observe apoptotic changes. Resultss 10-5、10-6、10-7 mol/L RA induced apoptosis in RPE cells.Cell shringkage,chromatin condensation and nuclear DNA fragmentation of RPE cells were observed by TUNEL technique.When 10-7、10-6、10-5mol/L RA treated RPE cells for 5 days,apoptotic index(AI)was 36.9%、4409% and 61.4% respectively,and 48.0%、59.9%、74.2% for 6 days.At the same concentration of RA,AI increased when time prolonged．At the same day,AI increased when the concentration of RA rose.There was significant difference in the results(Plt;0.05). Conclusion Our results showed that RA-induced apoptosis in RPE cells was detected with a good dose and time response. (Chin J Ocul Fundus Dis,1998,14:153-155)
Objective To investigate the regulative characterisitics of growth factors on proliferation of retinal pigment epithelial (RPE) cells in vitro. Methods Primary culture and subculture of RPE cells were establised in vitro Tumor.necrosis factor-alpha;(TNF-alpha;),interleukin-1beta;(IL-1beta;) and basic fibroblast growth factor (bFGF) in different concentrations were added to the RPE cells.3 H-thymidine(3 H-TdR) incorporation and a hemocytometer measured DNA synthesis and cell number separately. Results After RPE cells were separately treated with TNF-alpha;,IL-1beta; and bFGF,DNA synthesis was increased by 2.74,2.66 and 1.69 folds and cell number was increased by 54%,22% and 7amp; (Plt;0.05) respectively. When two growth factors were combined (TNF-alpha;+bFGF, IL-1beta;+bFGF),3.14,2.84 and 2.57 folds increased DNA synthesis significantly in each group (Plt;0.05). Compared with value by effect of two growth factors,the combination effect of three growth factors (TNF-alpha;+IL-1beta;+bFGF) was still ber (Plt;0.05). Conclusion The synergism of growth factors in their action might be one of the important roles in modulating the proliferation of RPE cells. (Chin J Ocul Fundus Dis,1998,14:95-97)