Objective To investigate the effect of somatostatin on the electrophysiological changes of early diabetic rats,and to clarify its therapeutic effects on retinopathy in early diabetic rats.Methods 20 Wistar male rats, which were induced into diabetic rat models by intraperitoneal injection of streptozotocin (STZ),were randomly divided into somatostatin therapy group and model control group, 10 in each group.The rats in somatostatin therapy group were injected with somatostatin 10μg·kg-1 ·d-1,for 8 weeks;the rats in model control group received the same volume of saline.Another 10 male Wistar rats were used as normal control group.The changes of blood glucose and electroretinogram were measured, and the indicators were used for statistical analysis. Results Compared with model control group,the blood glucose was declined in somatostatin therapy group at the 8th week (P<0.05).Compared with normal control group,the latent periods of a-wave,b-wave of rod-response and max-response were significantly extended in somatostatin therapy group and model control group at the 1 st, 2nd,4th,6th,and 8th week (P<0.05).The latent periods of a-wave,b-wave of rod-response and max-response in somatostatin therapy group were shorter than those in model control group at the 8th week (P<0.05 ). Compared with model control group, the amplitude had no changes at each observation time point in somatostatin therapy group (P>0.05).Conclusion Somatostatin has a therapeutic effect on early diabetic retinopathy in rats.