【摘要】 目的　探讨糖尿病状态下蛋白激酶 C(PKC)与内皮素 (ET)系统的改变 ,并采用特异性 PKC抑制剂观察对视网膜内皮素 - 1的影响。　方法　采用链脲佐菌素 (STZ)诱导早期糖尿病大鼠模型 ,酶联免疫吸附法 (EL ISA)测定大鼠视网膜内 PKC的表达 ,半定量逆转录聚合酶链反应 (RT- PCR)测定视网膜内内皮素 ET- 1、ET- 3、ET- A、ET- B受体 m RNA的表达 ,并通过玻璃体内给予 PKC抑制剂 GF10 92 0 3X观测对糖尿病大鼠视网膜内 ET- 1m RNA表达的影响。　结果　 2周糖尿病大鼠视网膜细胞膜 PKC活性明显增加 (t=3.2 96 ,P=0 .0 0 8) ,而细胞浆 PKC活性无明显改变 (t=0 .138,P=0 .894 ) ;糖尿病大鼠视网膜内ET- 1m RNA水平较正常组明显升高 (P=0 .0 0 8) ,而 ET- 3、ET- A、ET- B受体 m RNA水平则无明显改变(P=0 .918,P=0 .889,P=0 .5 0 0 ) ;糖尿病大鼠分别予以 10 - 5、10 - 6 、10 - 7mol/L PKC抑制剂 GF10 92 0 3X玻璃体内注射后 ,视网膜内 ET- 1m RNA水平较对照组下降 ,呈剂量 -反应关系。　结论　早期糖尿病大鼠视网膜内即存在 PKC的激活及 ET- 1表达的增加 ,而 PKC抑制剂可抑制 ET- 1的表达。更多还原

【Abstract】 Objective To investigate the alteration of protein kinase C (PKC) and endothelin system in early diabetic rats, and the effect of specific PKC inhibitor on the expression of retinal endothelin-1 (ET-1). Methods The rats model with streptozotocin(STZ)-induced diabetes were set up. The expression of retinal PKC was detected by enzyme-linked immunoabsorbent assay (ELISA). The expression of retinal ET-1, ET-3, ET-A and ET-B receptor mRNA was determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The alteration of retinal ET-1 mRNA after intravitreal injection of PKC inhibitor GF109203X in diabetic rats was also observed. Results The activities of membranous PKC were significantly increased in 2-week diabetic rats compared with that in normal rats(t=3.296, P=0 008), while activities of cytosolic PKC were unchangeable(t=0 138, P=0 894). The expression of retinal ET-1 mRNA was significantly increased(P=0 008), while no change was found in expression of ET-3, ET-A and ET-B mRNA(P=0 918,P=0 889,P=0 500). After intravitreal injection of 10 -5、10 -6、10 -7 mol/L PKC inhibitor GF109203X in diabetic rats, the expression of retinal ET-1 mRNA was decreased in a dose-dependent manner compared with the control rats. Conclusion Activation of PKC and increased expression of ET-1 could be found in the retina of early diabetic rats, and PKC inhibitor could inhibit the expression of retinal ET-1.更多还原