动物模型,糖尿病 z-bo 2020-08-03 685

　　[Model mechanism] In diabetes, when the retina is exposed to high concentrations of plasma glucose, free glucose accumulates in the cells to activate aldose reductase, which is the main enzyme for sorbitol metabolism and promotes the production of sorbitol . I will. It stimulates retinal capillaries. Pericytes, Muller cells of the retina, and certain special cellular components that accumulate sorbitol in them. The accumulation of sorbitol in the capillary wall can cause long-term hypertonicity of the blood vessel wall, stimulate the gradual thickening of the basement membrane, its stent function, cell adhesion and filtration dysfunction, pericyte death and arterioles. It may cause a collision. Similarly, exudative and bleeding changes can also lead to formation. [Modeling method] Animal model of streptozotocin (STZ): Dissolve streptozotocin in 0.1 mmol/L citric acid-sodium citrate buffer in an ice bath. Add 2.1 g of citric acid and double distilled water to 100 ml of liquid A, add trisodium citrate and 2.94 g of double distilled water to 100 ml of liquid B, mix 28 ml of liquid A and 22 ml of liquid B, dilute the mixture with distilled water to 100 ml lemon. The acid buffer with a pH of about 4.5 is placed in an ice bath for later use. A 10 g/LSTZ-DM solution was prepared in STZ, 55 mg/kg was injected intraperitoneally, and the rats were fasted for 12 hours before administration. All steps are performed under aseptic conditions, and the meal is resumed 30 minutes after the meal. After 72 hours, blood was collected from the tail and blood glucose was measured. The 10-week-old STZ-DM Prague Dawley rat can be used as an animal model closer to human early BDR for DR experimental research.

　　[Model Function] After successfully building the model, ERG starts to make changes. The amplitude of the ERG wave first increases and then decreases. As the O2 peak time value increases, the wave in OP will be displayed first, and then the amplitude of each wavelet in OP will be displayed. .. Pathological observations showed that capillary basement membrane was thick, finger-like protrusions of endothelial cells and phagocyte vesicles increased, pericyte mitochondria, bipolar and ganglion cells were swollen and found. Loss and vacuole-like changes reduce and expand the interganglionic disc retina, tortuous blood vessels, and expanded capillaries in the light-sensitive cell gap. The microstructure shows that lanthanum particles penetrate all layers of the retina (Figure 12-3), proliferate retinal capillary endothelial cells and thicken the basement membrane. [Model Evaluation and Application] The STZ-induced diabetic retina animal model induces a large amount of oxygen free radicals in the pancreas, leading to β cell damage, resulting in a decrease in blood insulin and an increase in blood glucose levels. Can establish and simulate human insulin-dependent diabetes model. The forming method is simple, economical, repeatable and fast. Therefore, it is worth noting that although most of the current induced diabetic retina animal models are established by the STZ method, not all established diabetic animal models have diabetic retinopathy. I will. It takes 1-3 days to establish the STZ-induced rat model, and the observation period is mainly 1-6 months. Whether all hyperglycemic animals show true DR in a short period of time should be closely monitored.