【Animal Modeling】-animal model of senile dementia (Alzheimer

  (1) Alzheimer's disease model caused by β-amyloid 1-42

  1. Model material animal: healthy Wistar rat, weight 260-290g, age 16-17 weeks, male and female; drug: β-amyloid 1-42 (β-amyloid 1-42, Aβ1-42), sulfur Diflavin S; Equipment: ALZET miniosmoticpumps 2004, rat brain positioning device, Strong90 micro-motor dental drill (Korea).

  2. The modeling method is PeBegrino et al. Use the localization map of the rat brain. The width of Daquan Gate is 1.5 mm, the rear is 2.0 mm, and the lower is 3.0 mm. Pentobarbital (40 mg/kg) was injected intraperitoneally to anesthetize the rat and open the scalp. After positioning, use a dental drill with a diameter of 2 mm to drill a small hole in the skull, keeping the dura mater intact. The experimental group was perfused with Aβ1-42 (200g/d) on the side of the ventricle of the ALZET mini osmotic pump for a long time, and the control group was perfused with the same amount of normal saline. The needle was fixed on the skull with dental cement, and the ALZET mini osmotic pump was placed under the skin of the rat’s neck.

  3. Modeling principle Aβ generates excitatory drugs, oxygen free radicals and oxidative stress by activating protein kinases, which directly or indirectly leads to the development of Alzheimer's disease (Alzheimer's disease, AD).

  4. Histological examination of biochemical and pathological changes after modeling: The experimental group showed that there were many amyloid plaques (SP) deposits and neurofibrillary tangles (NFT) formation in the hippocampus and cortex, and the control group showed a large number of amyloid plaques (SP) deposits and neurofibrillary tangles (NFT). Deposits without amyloid plaques and neurofibrils tangled in rats.

  5. Precautions Strictly disinfect surgical instruments to prevent surgical infection, surgical trauma should be as small as possible, and strict aseptic operations should be performed. Pay attention to the depth when drilling the skull. If there is a breakthrough, stop immediately. Prevent heavy bleeding. After surgery, the rats can be separated and awakened for 3-5 hours, and then placed in a cage to prevent the first awakened rat from licking or biting the wound of the unconscious rat. In the breeding room, try to maintain the best temperature and humidity for the rats.