Objective　To investigate the effect of pigment epitheliumderived factor (PEDF）on the expression of glutamine synthetase in retinal M uuml;ller cells of diabetic rats.Methods　Diabetic rats were induced with streptozotocin injection.Before and after injection of 10  mu;l (0.1  mu;g/ mu;l) PEDF (experimental group) or 10  mu;l PBS (control group) into the vitreous cavities of diabetic rats respectively for 48 hours,the expressions of GS and IL-1 beta; in retina were analyzed by immunohistochemistry and real time RTPCR techniques. After being treated with 100 ng/ml PEDF for 24 hours in high glucose conditions,the expressions of GS and IL-1 beta; in cultured M uuml;ller cells were studied by western blot and real time RT-PCR techniques. Apoptosis was analyzed by flow cytometry after Annexin V fluorescein isothiocyanate/Propidium idoium (Annexin V-FITC/PI) staining.Results　By immunohistochemistry (the protein level) and real time RT-PCR (the mRNA level),it was found that the expression of GS decreased and the expression of IL-1 beta; increased obviously (real time RT-PCR：GS:t=4.23,P＜0.01；IL-1 beta;:t=16.73,P＜0.01；immunohistochemistry：GS: t=5.13,P＜0.01；IL-1 beta;:t=9.32,P＜0.01) in diabetic rats. After injection of 10  mu;l (0.1  mu;g/ mu;l) PEDF into the vitreous cavities of diabetic rats for 48 hours,it was found that the expression of GS increased and the expression of IL-1 beta; decreased significantly(RT-PCR GS:t=3.87,P＜0.01IL-1 beta;:t=3.61,P＜0.05;immunohistochemistry:GS:t=3.32, P＜0.05；IL-1 beta;: t=2.63,P＜0.05). Under high glucose conditions, 100 ng/ml PEDF induced decreasing expression of IL-1 beta; and increasing expression of GS significantly (RT-PCR：GS: t=2.89, P＜0.05；IL-1 beta;: t=3.37,P＜0.05；Western blot：GS:t=2.66,P＜0.05;IL-1 beta;:t=3.23,P＜0.05).Apoptosis of M uuml;ller cells under high glucose conditions was inhibited significantly by the treatment with 100 nmol/ml PEDF (t=3.21,P＜0.05). Conclusions　In diabetic rats,PEDF may decrease expression of IL-1 beta; in rat retinal M uuml;ller cells, which may result in increasing expression of GS.To some degree,it inhibits possibly the death of retinal ganglion cells.

Citation： 沈玺,焦秦,钟一声,谢冰. The effect of pigment epithelium derived factor on expression of glutamine synthetase in diabetic rat retina. Chinese Journal of Ocular Fundus Diseases, 2010, 26(2): 155-159. doi: Copy