Objective To investigate the protective effect of aminoguanidine(AG),silymarin (Sil) and anisodamine (Ani) on retinal capillary pericytes cultured in glycosylation products. Methods MTT cololrimetric assay, [3H] thymidine incorporating and fluorescent indicat or fura-2 acetoxy-methyl ester (Fura-2AM) were used to study the influence of AG,Sil and Ani on the growth,DNA synthesis,and cytosolic free calcium ([Ca2 ]i)changes of pericytes cultured in the medium contained early glycation products (EGs) or advanced glycation end products (AGEs). Results Cultured in the medium contained EGs,the A value by MTT assayed and amount of [3H] thymidine incorporating in AG group and Sil group were obviously elevated than those of control group(Plt;0.01);but the [Ca2 ]iconcentration in both groups were decreased significantly comparing with control group(Plt;0.01 and 0.05).Under the condition of AEGs,only AG group was distinctly increased on the A value and amount of [3H] thymidine incorporatin g (Plt;0.01),and [Ca2 ]i concentration was markedly decreased (Plt;0.05) comparing with control group. Conclusion AG has the portective effect on pericytes against the proliferative inhibition and excessive elevation of [Ca2 ]i concentration in cytosol which are induced both by EGs or AGEs.Silymarin has the effect for those only by Egs-induced.Ani has no protective effect no pericytes nei ther cultured in medium with EGs nor with AGEs. (Chin J Ocul Fundus Dis, 2001,17:192-194)
Objective To investigate the effects of glycation pro ducts on growth and cytosoic free calcium (［Ca2+］i) of bovine retinal capillary pericytes. Methods The changes of growth and ［Ca2+］i of bovine retinal pericytes,which were cultured in early glycation products of bovine serum albumin (EG-BSA) and advanced glycation end products of bovine serum albumin (AGE-BSA),were studied by counting cell numbers,MTT colorimetric assay,［3H］thymidine incorporating,and fluorescent indicator fura-2 acetoxymeth1 ester (Fura-2AM). Results The number of alive pericytes in groups of EG-BSA and AGE-BSA were 17.87plusmn;2.36 and 14.77plusmn;3.72 which comparing with their control groups (20.54plusmn;0.82 and 20.31plusmn;0.93)were de creased 13．00% and 27．00% (Plt;0.01) by counting cell numbers on a counting plate after four days.The results were 0.4619plusmn;0.0946 and 0.3884plusmn;0.1031 which comparing with their control groups (0.5236plusmn;0.0539 and 0.5227plusmn;0.0519)were decreased 12．00% and 25.70% (Plt;0.01) by MTT colorimetric assay.Amount of ［3H］thymidine incorporating in groups of EG-BSA and AGE-BSA were 39450.16plusmn;887 0.68 and 33667.85plusmn;10581.70 which comparing with their control groups (56373.63plusmn;2317.97 and 56542.04plusmn;1961.23)were decreased 30．00% and 40.40% (Plt;0.01).The ［Ca2+］i concentration of pericytes in groups of EG-BSA and AGE-BSA were (129.55plusmn;30.41) nmol/L and (179.71plusmn;56.69) nmo l/L which comparing with their control groups ［(79.70plusmn;6.94) nmol/L and (83.plusmn;6.39) nmo l/L］ were increased to 163．00% and 214．00%. Conclusion Both EG-BSA and AGE-BSA can inhibit the proliferation and DNA syntheses of retinal capillary pericytes,and increased ［Ca2+］i concentration in pericytes,especially the AGE-BSA. (Chin J Ocul Fundus Dis，2000，16：139-212)
OBJECTIVE:To observe the effect of dexamethasone to intracellular free Ca2+ of frozen RPE cells. METHODS:The cultured human RPE cells were frozen for 30s at --70deg;C. The RPE cells were loaded with Fura-2/AM and analyzed using a digital imaging microscopy system,the effect of dexamethasone to intracellular free Ca2+ was measured at a serial concentration of 40, 60,100,150,200mu;g/ml. RESULTS:The concentration of intracellular free Ca in frozen human RPE cells was increased to 18.6%~29.8% by dexamethasone at concenlration of 40mu;g/ml~60mu;g/ml,while was decreased to 28.4%~35.2% at 150mu;g/ml~200mu;g/ml. CONCLUSIONS:Effect of dexamethasone showed two aspects of effect to frozen cultured human RPE ceils,that it was inhibitor at high concentration and stimulator at low concentration （Chin J Ocul Fundus Dis,1997,13: 86-88）
PURPOSE:To approach the establishment of t be optimal method for determining the intracellular free Ca2+ concentration[Ca2+]i of dissociated newborn rabbit retina cells by using fluorescent indicator-Fura-2/AM. METHODS:Trypsin was employed to prepare the retlna cell suspensions which were then loaded with Fura-2/AM followed by fluorescence determination. RESULTS:The cellular viability rate of retina cell suspensiotls prepared by 0.05% trypsin 10 minutes at 37deg;C was over 90%. Loading the retina cell suspensions with Fura-2/AM 40 minutes at 37deg;C and then measurlng the fluorescent intensity of the suspensions within 30 minutes were proved to be the optimum. CONCLUSIONS:The resting [Ca2+]i of retina cell suspension was (223plusmn;27)nmol/L whlch was within the expected range of [Ca2+]i level. 25mmoI/L and S0mmol/L K+ increased the [Ca2+Ji 59% and 148% respectively. These results indicate that the preparation of retina cell suspensions and the method of [Ca2+Ji determination are reliable and feasible. （Chin J Ocul Fundus Dis,1996,12: 108-110 ）