动物造模,慢性实验性癫癎模型 z-bio 2021-04-01 391

　　(1) Replication method Healthy male rats weigh 250-300g. After intraperitoneal injection of chloral hydrate (350-400 mg/kg body weight dose) or pentobarbital sodium (50-60 mg/kg body weight dose) anesthetized, it was fixed in a stereotactic fixture. Cut off the hair on the crown and disinfect the skin at the surgical site. Under aseptic conditions, a 1 cm incision was made in the skin along the midline, and the 3D coordinates of the amygdala were marked according to the rat location map (coordinate arrangement: AP2mm, ML2mm, DVR8.5mm). Use a small dental drill to drill a hole on the surface of the bone, and then slowly insert an 8.5 mm long amygdala stimulation electrode into the amygdala. At the same time, place 4mm on the left and right sides of the midline of the skull, place the four radio wave recording electrodes 10mm in the front and back direction, with an insertion depth of 2mm, and fix the electrodes in dentistry. powder. In order to prevent the electrodes from falling off, some small screws can be placed on the occipital and frontal bones and fixed with denture powder. After the operation, kanamycin (125 mg/day per animal) or gentamicin (20,000 U/day per animal) was injected intramuscularly for 3 days to prevent infection. It can be used for experiments after one week.

　　Give the rat one electrical stimulation at a fixed time every day. Each stimulus is 3 seconds. The stimulation intensity starts from 80μA and increases by 80μA every day until the stimulated area is discharged. At this time, the current is the current after discharge. If repeated stimulation does not cause electric discharge in the rat, it will eventually fail to form a shooting effect. Therefore, it is necessary to select a mouse to measure the current after discharge in the experiment.

　　(2) The model is characterized by repeated electrical stimulation of sub-convulsive doses in specific parts of the brain, which eventually leads to intense partial or generalized seizures. The limbic system is the most commonly used electrical stimulation site. Once the ignition is formed, it can last a long time or even a lifetime. The functions of this model are as follows: (1) The regularity of cortical waves and seizures can be maintained for more than one year without electrical stimulation. ②Restimulation may cause clonic seizures. ③A few animals will attack naturally. ④Seizures are caused by transmission between synapses. It is now believed that the ignition model is the result of repeated electrical stimulation leading to increased release of endogenous glutamate, sensitizing NMDA receptors and increasing their number. It can cause fire in many animals, but rats are usually used. The amygdala is the most sensitive part of the stimulus, followed by the globus pallidus, hippocampus and pear-shaped area. However, the network structure of the red nucleus, substantia nigra and brain stem is not sensitive. The standard state of electrical stimulation is that the current wavelength is 1 ms, the frequency is 60 Hz, and the duration is 1 ms. Among them, the ignition effects of 25, 60 and 150 Hz are the same. Stimulus intensity: Take the amygdala as an example. It is 50-400μA for rats, 100-1000μA for cats, and 200-600μA for monkeys and baboons.

　　(3) The comparative medical epilepsy model is now regarded as a complex local epilepsy model, which is closely related to humans and has been widely used. According to the literature, many animals, such as frogs, reptiles, mice, rats, rabbits, dogs, cats, rhesus monkeys, and chickens, can be used as ignition models. Seizures in the amygdala and other marginal kindling models usually go through five stages: grade 1, facial clonus, and grade 2. Rhythmic Rhythm of Facial Rhythm; Grade 3. Facial clonus, nodding, limb clonus; grade 4, grade 3 + standing on hind limbs, grade 5, grade 4 + fall. Grades 4 and 5 can be used as models for secondary systemic epilepsy. Once the connection is established, the susceptibility and convulsive behavior of brain cells can be maintained for a long time in animal life, so as to study the formation mechanism of neuronal hyperexcitability and the maintenance and development of hyperexcitability in epilepsy. the study. At the same time, the model is easy to establish and low in cost, and it is more sensitive and practical than ordinary animals and other models in screening new antiepileptic drugs and detecting their side effects.