Animal model of diabetic nephropathy
Animal model of diabetic nephropathy
The incidence of diabetes mellitus in our country and the world has shown a significant rising trend, diabetic nephropathy (DN) is one of the manifestations of diabetes mellitus systemic microangiopathy, is a common complication of diabetes mellitus, and it has become the second largest cause of end-stage renal disease in our country. At present, there is no ideal animal mordels of diabetic nephropathy at home and abroad.
Principle
Depending on the experimental method, the corresponding principles are different:
The basic principles of animal models of diabetic nephropathy: Type 1 diabetic nephropathy models are mostly studied using high-dose streptozocin (STZ)-induced animal models, while type 2 diabetic nephropathy models are mostly replicated on the basis of high glucose and high fat chow-fed rats inducing insulin resistance in combination with repeated intraperitoneal injections of low-dose streptozotocin (STZ), which is similar to the rat model of type 2 diabetes mellitus (T2DM) in human beings. Unilateral nephrectomy contributes to accelerated renal disease, but unilateral nephrectomy induces hemodynamic and other alterations, which superimpose on the hemodynamic disturbances of renal tissues in the hyperglycemic state, and can have an impact on the model establishment. Appliance The common application areas of animal models of diabetic nephropathy are as follows: Early diagnosis of diabetic nephropathy is important for preventing its progression to end-stage renal failure. The pathogenesis of diabetic nephropathy has not been completely justified. Therefore, the establishment of animal models of diabetic nephropathy can be used to explore the cellular and molecular mechanisms of diabetic renal damage, and provide theoretical support for early diagnosis and early intervention of diabetic nephropathy. Operation method Animal model of diabetic nephropathy Principle Type 1 diabetic nephropathy models are mostly studied using high-dose streptozocin (STZ)-induced animal models, and type 2 diabetic nephropathy models are mostly replicated by repeated intraperitoneal injections of low-dose streptozocin (STZ) in combination with high-glucose, high-fat chow-fed rats with induced insulin resistance to resemble the human type 2 diabetes mellitus (T2DM) rat model. Unilateral nephrectomy contributes to accelerated renal pathology, but unilateral nephrectomy induces hemodynamic and other alterations, which superimpose on the hemodynamic disturbances of renal tissues in the hyperglycemic state, and can have an impact on model establishment. Materials and Instruments Subjects: Move The basic process of animal models of diabetic nephropathy can be divided into the following steps: Caveat 1. non-fasting blood glucose ≥ 16.7 mmol/L measured by blood sampling at the tip of the nidus after 72 hours. 2. a decrease in GFR of more than 50% over the entire survival period. 3. more than 100-fold increase in urinary protein in modeled animals compared to controls of the same sex and age of the same strain (i.e., orthostatic controls). 4. pathological changes by electron microscopy, including glomerular mesangial sclerosis (increase in glomerular mesangial volume by more than 50%), vitreous degeneration of small arteries, thickening of the glomerular basement membrane by more than 25%, and tubulointerstitial fibrosis. 5. On light microscopic examination, pathological changes mainly include marked increase in glomerular volume, dilatation of the medullary lumen, widening of the tunica albuginea stroma, thickening of the basement membrane, tunica albuginea and sclerosis, thickening of the basement membrane, foamy endothelial cell degeneration, hyalinization of accessory glomerular arterioles, and damage to askatric blood vessels. No diabetes model bubble has yet met the first two criteria, but many studies have shown pathological changes that meet or approach the pathological criteria. For more product details, please visit Aladdin Scientific website.
① 8-10 weeks clean grade healthy male: Wistar or SD rats, weighing 180~220 g were selected.
Experimental reagents:
① 50 mmol/L;
② Sodium citrate buffer, pH 4.5, prepared before use;
③ Streptozotocin (STZ); ④ 10% (w/v) sucrose: prepared before use.
Equipment:
① Rat cage, metabolic cage;
② Temperature, humidity and light-controlled rearing room;
③ 1.5 mL EP tubes;
③ 1.5 mL EP tube; ④ Code foil;
⑤ 2.5 mL syringe;
⑤ 2.5 mL syringe; ⑥ simple blood glucose meter and blood glucose test strips.
(I) Process 1
animal models of type 1 diabetic nephropathy
(1) Clean-grade healthy male Wistar rats were selected and housed in separate cages, and were given an ad libitum diet with water intake to maintain good ventilation and a constant temperature (18~21 ℃). They were given free diet, water, good ventilation, constant temperature (18~21 ℃), and 12-hour alternate lighting. The rats were acclimatized and fed for 1 week, and the night before STZ injection was fasted with no food or water (more than 12 hours of fasting). The rats are weighed and the required dose of STZ is calculated according to their body weight at 40~65 mg/kg.
(2) Prepare the solution before STZ injection: Liquid A (0.1 mol/L citrate buffer): dissolve 2.14 g of citric acid in 100 mL of distilled water; Liquid B (0.1 molL sodium citrate solution): dissolve 2.94 g of trisodium citrate in 100 ml of distilled water; the two solutions are prepared into a citrate buffer solution (pH 4.2-4.5) at the ratio of A:B = 1:1.32. The solution was stored at 4 ℃. The final concentration of STZ was 1%, i.e., 20 mg STZ + 2.0 mL citrate buffer, which was prepared on the spot. The final concentration of STZ injection was 1%, i.e., 20 mg STZ + 2 0 mL citrate buffer. Dissolve and inject into the rat intraperitoneally within 5~8 minutes.
(3) After taking the required STZ solution from the syringe, wrap it in tinfoil and rapidly inject it intraperitoneally into the corresponding rats. The rats injected with STZ were immediately given 10% sucrose water to drink, and then changed to normal drinking water on the second day.
（ Process 2
animal models of type 2 diabetic nephropathy
(1) Healthy male Wistar rats of clean grade were housed in separate cages with free diet and water intake, good ventilation and constant temperature (18~21 ℃), and 12 hours of alternating lighting. Adaptive feeding was performed for 1 week. The rats were fed a high-sugar and high-fat diet (20% sucrose, 15% lard, 2.5% cholesterol, 0.5% cholate) for 1-2 months.
(2) The night before the STZ injection, the rats were fasted without food or water (more than 12 hours of fasting). Rats were weighed and the dose of STZ was calculated based on body weight at 20-45 mg/kg.
(3) Prepare the solution before STZ injection: Liquid A (0.1 mol/L citrate buffer): dissolve 2.14 g of citric acid in 100 mL of distilled water; Liquid B (0.1 mol/L sodium citrate solution): dissolve 2.94 g of trisodium citrate in 100 mL of distilled water; prepare citrate buffer (pH 4.2~4.5) at the volume ratio of A:B = 1:1.32 and store at 4℃. The solution was stored at 4 ℃. The final concentration of STZ was 1%, i.e., 20 mg STZ + 2.0 mL citrate buffer, which was prepared on the spot. The final concentration of STZ injection was 1%, i.e., 20 mg STZ + 2 0 mL citrate buffer. Dissolve and inject into the rat intraperitoneally within 5~8 minutes.