动物造模,记忆获得障碍模型 z-bio 2023-01-13 580

　　(1) Scopolamine-induced memory impairment model

　　1. Modeling materials Animals: healthy Kunming mice; drugs: scopolamine; equipment: MR-921 mouse jumping platform experiment automatic recorder.

　　2. Method of modeling Scopolamine was injected intraperitoneally with 3mg/kg of scopolamine, and the platform jumping training was started 10 minutes later. The next day, test the memory score.

　　Jumping platform method: first place the mouse in the platform platform, adjust to the environment for 5 minutes, and place it gently on the platform. When the animal jumps off the platform and touches the copper grid with its limbs, it is stimulated with a 40V AC voltage, and the EL value of the mouse is recorded. , And record the number of electric shocks (the number of errors) within 5 minutes as the academic record. The test was carried out after 24 hours. The mouse was placed on the platform, and its SDL value and the number of electric shocks received within 3 minutes (the number of errors) were recorded to evaluate its memory ability. During the test, if the mouse stays on the platform for more than 3 minutes, its incubation period is counted as 180s.

　　3. Principles of Modeling The synaptic mechanism in the brain of memory impairment caused by scopolamine may be related to the decrease of protein synthesis in the synapses of the cholinergic nervous system in the brain, which in turn leads to changes in the structural parameters of the synaptic interface.

　　4. The jumping platform experiment after model building shows that compared with the control group animals, the number of errors during learning in the normal control group is (2.16±1.15) times, the number of errors during memory is (0.33±0.50) times, and the latency period is learning. (EL) is (13.8±4.7)s, memory (SDL) is (155.6±49.3)s; the number of errors in learning of the model group is (6.38±2.62) times, the number of errors in memory is (2.16±1.13) times, latency Learning is (25.6±7.1)s, memory is (58.3±21.6)s, academic performance is poor, manifested by prolonged reaction time and increased number of errors.

　　(2) Pentobarbital-induced memory impairment model

　　1. Modeling materials Animal: healthy Kunming mice; drug: pentobarbital.

　　2. Modeling method 30 minutes before training, intraperitoneal injection of 15mg/kg pentobarbital, continuous training for 5 days, still administered once a day during training, each training can measure its directional discriminative learning and memory function, or Intraperitoneal injection of 30 mg/kg 30 min before training or 20 mg/kg pentobarbital intraperitoneal injection of 20 min before training can cause memory impairment.

　　3. Principles of Modeling Pentobarbital is a central inhibitor, which mainly causes directional discriminative learning and memory disorders.

　　4. Changes after modeling. After modeling, the direction-discriminatory learning and memory function test was performed by the electric maze method. The number of errors in the blank control group was (3.3±1.7) times; the number of errors in the model group was (5.7±2.1) times, indicating memory acquisition obstacle.

　　(3) Anisodine-induced memory impairment model in mice

　　1. Modeling materials Animals: NIH juvenile mice, 16-18g; medicine: anisodine; equipment: platform platform.

　　2. Modeling method 20min before training, 10mg/kg anisodine was injected into the abdominal cavity, and the learning and memory function was measured after training.

　　3. Principles of Modeling Anisodine-induced learning and memory disorders in direction discrimination.

　　4. Change measurement results after model building, control group: the incubation period is (293.2±94.5) s, the number of errors within 5 min is (0.3±0.6); the model group: the incubation period is (69.5 ± 102.7) s, the number of errors within 5 min is (1.6±1.4) times. The results showed that compared with the control group, the incubation period of the model group was significantly shortened, and the number of errors within 5 minutes increased significantly, indicating that the intraperitoneal injection of anisodine has caused memory impairment.

　　(4) Aluminum chloride-induced learning and memory impairment model in animals

　　1. Modeling materials Animals: Kunming mice, both male and female, body weight (22±2) g; drug: aluminum chloride; equipment: micro-injector, platform platform.

　　2. Modeling method The model mice were injected with pentobarbital 40mg/kg into the abdominal cavity. After anesthesia, the skin on the top of the head was disinfected with iodine and alcohol. Insert a micro-syringe 1 mm after the breg-ma) point and 2 mm away from the midline to perform intraventricular injection with a needle depth of about 2.5 mm. The left ventricle was injected on the first day, and the blank control group was injected with 2μl of normal saline per mouse. The other groups were injected with 2μl of 1% AICl3 per mouse. At 48 hours after the first intraventricular injection, the passive avoidance conditioned response experiment was carried out by the platform jumping method, and the incubation period and the number of errors were recorded.

　　3. Principles of Modeling Intraventricular injection of aluminum chloride can inhibit the conditioned avoidance response and cause learning and memory disorders in animals.

　　4. Test results of changes after model building: The incubation period of the animals in the control group was (238.58±86.82)s, the model group was (142.63±111.63)s; the number of errors in the control group was (0.58±0.79) times, and the model group was (1.75±1.49) ) Times. The results showed that the incubation period of the model group mice was significantly shortened, the number of errors increased, and learning and memory disorders appeared.

　　(5) A model of learning and memory impairment induced by β-starch peptide fragments

　　1. Modeling materials Animals: SD rats, weighing 280-320g; drugs: β-amyloid polypeptide, pentobarbital; equipment: incubator, micro-injector.

　　2. Modeling method The β-starch polypeptide is prepared to a certain concentration with sterile physiological saline and stored at -20°C. Before use, place the β-starch polypeptide solution in an incubator at 37°C for 7 days to form aggregated β-starch polypeptide. Take SD rats, both male and female, anesthetized with pentobarbital, hair removal on the top of the head, disinfection of the skin and incision, fixed on a stereotaxic instrument, and injected β-starch peptide solution into the hippocampus on both sides. The injection point is positioned: AP=- 3.5mm, ML=±2.0mm, DV=2.7mm, the micro-injector inserts the needle vertically, the injection is completed within 5 minutes, the needle is retained for 5 minutes, and the needle is slowly raised. After local disinfection, the skin was sutured and antibiotics were injected intramuscularly to fight infection. Raised in a single cage until the rats are fully awake. After 3 days, a behavior measurement experiment was performed.

　　3. Modeling principle Alzheimer's disease is mainly manifested by progressive memory loss and mental retardation. One of its neuropathological characteristics is: cerebral cortex atrophy, the existence of a large number of senile plaques composed of β-amyloid protein outside the cell, and the cortex Vascular amyloidosis of arteries and arterioles. Therefore, the use of β-amyl peptides into the hippocampus of rats can replicate animal models of learning and memory dysfunction.

　　4. Biochemical changes after model building The platform jumping method was used to test the changes in the learning and memory function of the animals, and the number of electric shocks in the rats within 5 minutes, namely the cumulative number of errors (Ns), platform residence time and cumulative stimulation time (Ts) were recorded. The platform residence time, Ts, and Ns of the blank group were 293.0±18.52, 6.5±3.2, 0.125±0.35, respectively; the β-amyl peptide group were 254.1±3.77, 44.3±4.2, 1.125±0.83, respectively, which was significant compared with the blank group difference.

　　5. Precautions Strictly sterilize surgical instruments to prevent surgical infection, surgical trauma should be as small as possible, and strictly aseptic operation. Keep the animal's optimum temperature and humidity as much as possible in the breeding room.

　　(六)Sodium azide-induced learning and memory impairment model

　　1. Modeling material animal: SD rat, male, 3 months old, body weight (300±22) g; drug: sodium azide solution (sodium azide is prepared with sterile saline) 240mg/ml; device: micropump .

　　2. Method of modeling Sodium azide is prepared as a 240mg/ml solution with sterile physiological saline, 2ml of liquid is accurately sucked into the micropump capsule, and the flow regulator is slowly inserted into the capsule. After the rat is anesthetized, incise the skin 1 cm parallel to the spine at 1 cm from the center of the back of the rat to the right and downwards, and bluntly separate the skin by 2 to 3 cm to the cephalic side. , Suture the skin and release 2mg/kg per hour for 30 days.

　　3. Principles of Modeling Mitochondrial defects are closely related to a variety of neurodegenerative diseases. Among them, long-term and slow inhibition of cytochrome C oxidase (COX) can cause learning and memory disorders. Therefore, the use of mitochondrial cytochrome c oxidase inhibitor sodium azide can cause learning and memory disorders.

　　4. Changes after modeling. Learning and memory dysfunction appeared after 4 weeks.

　　5. Precautions All operations must be performed aseptically.