Selection Of Combined-drugs For Preventing And Treating PVR In Vitro

Proliferative vitreoretinopathy(PVR)is the most common cause of failure of retinal reattachment surgery. It is also a kind of serious disease causing blind. Despite the researches on preventing and treating PVR have developed fastly, the vitrectomy is still an effective method and is used widely now. As vitreoretinal surgical techniques have advanced and new apparatus are inrented continually, the success rate of surgery has been increased remarkably. Thus, almost always, the retina can be reattached at the time of surgery, however , recurrent detachment is common, and is usually caused by recurrent proliferation. This suggests that preventive pharmacological treatment is needed. The drugs that act on multiple stimulatory factors are researched widely. Because cellular proliferation is the main pathologic process in PVR, attention has focused on the antiproliferative drugs. Of the proliferative cells which are involved in PVR, the retinal pigment epithelial (RPE) cells play a key roll. In this study, we experimented with cultured rabbit retinal pigment epithelial cells to test the effects of three kinds of drugs for inhibition of cellular proliferation in PVR. As the combined drugs may increase the effects of drugs and decrease the sideeffects of drugs, we selected effective and secure combined drugs in order to use them in clinic, and to prevent or adjunctively to treat PVR in the future.Objective:To determine the antiproliferative effect of IC25 and IC50 of retinoic acid(RA), Trifluoperazine(TFP)and Quercetin. Combine them with each other ,and observe their inhibitive effect and security on cultured rabbit RPE cells in vitro. Select effective and secure combination through our experiments. Methods:1.RPE cells were isolated from mature pigmented rabbit eyes and were cultured with trypsin enzyme digesting technique and passaged in vitro.2.120 hours after co-cultured with single drug in different concentration, the proliferation of cells were analyzed with MTT colormetric method on 490nm.3.Worked out the IC25 and IC50 of those tested drugs and combined them with each other.4.120 hours after co-cultured with combined drugs, the proliferation of cells were analyzed with MTT colormetric method on 490nm.5.The viability of cells was determined by trypanblue exclusion, light microscope and transmission electron microscope.Results:1. 72 hours after co-cultured with IC50 of RA combined withIC50 of quercetin or IC50 of TFP combined with IC50 of quercetin, the cells all died.2. 120 hours after co-cultured with IC50 of RA combined with IC50 of TFP, and IC25 of TFP combined with IC50 of quercetin, cells showed seriously degeneration and necrosis.3. 120 hours after co-cultured ,the rate of inhibition showed no significant difference between using IC50 of RA combined with IC25 of quercetin and using IC50 of RA(P=0.413).4. 120 hours after co-cultured, the rate of inhibition(%)of IC50 of RA combined with IC25 of TFP and IC50 of TFP combined with IC25 of quercetin are respectively 80.3855±0.5693(P＜0.01) and 79.50±0.9985(P＜0.01).The viability(%)of cells in these two groups are 97.58±8.33 and 97.58±5.00 respectively. No degeneration or necrosis was found with light microscope or transmission electron microscope.Conclusion:1. IC50 of RA combined with IC25 of TFP and IC50 of TFP combined with IC25 of quercetin are both more effective and more secure than single drug in inhibiting the proliferation of rabbit RPE cells in vitro.2. Combination of some drugs can both decrease the concentration of single drug and increase the effects without significant side effects. It may be a valuable method to prevent and treat PVR.