Experimental Study, 1 Sugar Network, And Treating Early Diabetic Retinopathy In Rats

Diabetes mellitus (DM) has become the public health problem that is concerned by many countries all over the world. Diabetic retinopathy (DR) is one of the most common and important diabetic microvascular complications, and has close relationship with other chronic diabetic complications. As DR usually predicts how serious the pathologic changes of the blood vessels and the nervous system are, it is important and significant to study the possible pathogenesis and the treatment of DR in order to study the prevention and the treatment of other chronic diabetic complications.Objective : To investigate on the mechanism of the prevention and cure of DR by the TCM decoction named TWYHD (Tang Wang Yi Hao decoction) through observing the ultrastructural pathological changes in retinal capillaries in early diabetic rats,and the influence of TWYHD on the ultrastructure in the retinal capillaries.Methods : The rats with diabetic induced by streptozotocin(STZ) were divided randomly into 4 groups: diabetes model group(M), Metformin Hydrochloride group(A), small dose preparation group of TWYHD(B), and large dose preparation group ( C ) .Normal control group(CON) was also set. After 6 months, a comparison was made on the parameters of blood rheology and the levels of blood sugar of 5 groups. Sections were taken from the rat retinas, some were made into retinal digest preparations and observed by light microscope, some were observed under transmission election microscope.Results : After 6 months, there was a obviously coacervation and viscousness status of the diabetic rats. The retinal digest preparations of the STZ-diabetic rats showed characteristic retinal changes of early diabetic retinopathy, including decrease of pericytes, microaneurysm, acellular capillary and pericyte ghost.Retinal changes and all of the parameters which related to the blood rheology were much better in the treated group with TWYHD than in the model group, and the treated groups with medicine, such as B and C, were better than A, especially C was very similar with the CON(normal group). Conclusion : There have been early diabetic retinopathy changes in retina of early STZ-diabetic rats. Early treatment with TWYHD, especially prevention and cure at very early period, may be helpful in delaying or possibly preventing the diabetic retinopathy. Its curative effect is better than that of the group of Metformin Hydrochloride. The result of our study shows that TWYHD can effectively control the development of early diabetic retinopathy, and may also has good curative effect on diabetic microvascular complications.