Retinal pigment epithelial(RPE) cells play a important role in proliferative retinopathy(PVR) by the collagen production involved in the formation of PVR membrane. To evaluate the effect of L-azetidine-2-carvoxylic acid(LACA), a proline analogue, known as depressing the abnormal cell proliferation and PVR membrane formation, we examined the proliferation, collagen synthesis and migration of cultured bonine RPE cells following the addition of LACA. Differant concentrations of LACA as 1, 10, 50, 100microgram/ml was added to bovine RPE cells and cultured. The cell numbers were measured in 3, 6, 9 days, [3H]-thymidine uptake assay was done to evaluate the change of DNA synthesis, and collagen synthesis and cell migration was measured. The proliferation of PRE cells treated with LACA were significantly inhibited in a concentration and time dependant manner. [3H]-thymidine uptake and collagen synthesis of RPE migration was also significantly inhibited in proportion to the concentration. The results reveal that LACA has an inhibitory effect on cell proliferation, collagen synthesis and migration of bovine retinal pigment epithelial cells. It also suggest that the use of LACA to suppress membrane formation in the eyes with PVR can be possible.
Cell Count ; Cell Movement ; Cell Proliferation ; Collagen* ; DNA ; Epithelial Cells* ; Meclizine ; Membranes ; Proline ; Retinaldehyde* ; Vitreoretinopathy, Proliferative

The course of diabetic retinopathy following cataract extraction was studied prospectively in 45 eyes of 33 diabetics for 4-50 weeks(average duration: 20 weeks). The results were as follows: 1. Twenty two(81.4%) of the 29 eyes with preoperative existence of diabetic retinopathy showed a statistically higher incidence of postoperative progression of diabetic retinopathy than eight(50%) of the 16 eyes with no pre-existing diabetic retinopathy(p<0.05). 2. Ten(83.3%) of the 12 eyes with posterior chamber lens in the sulcus showed a statistically higher incidence of postoperative progression of diabetic retinopathy than sixteen(55.2%) of the 23 eyes with posterior chamber lens in the bag(p<0.05). 3. The final corrected visual acuity of better than 20/40 was achieved in eleven(68.7%) of the 16 eyes with no pre-existing diabetic retinopathy and in ten(58.8%) of the 17 eyes with nonproliferative diabetic retinopathy. It revealed no significant difference between them(p>0.05). 4. Nephropathy is the most common preoperative systemic disease and eighteen of the 19 eyes showed the postoperative progression of diabetic retinopathy. There was no statistically significant difference regarding fasting blood sugar, pp2hr, HbA1c, total cholesterol, triglyceride, or the presence of hypertension, atherosclerosis, cardiac disease, and anemia. The only significant difference was related to the presence of nephropathy(p<0.05).
Anemia ; Atherosclerosis ; Blood Glucose ; Cataract Extraction ; Cataract* ; Cholesterol ; Diabetic Retinopathy* ; Fasting ; Heart Diseases ; Hypertension ; Incidence ; Prospective Studies ; Triglycerides ; Visual Acuity