动物造模,慢性实验性癫癎模型 z-bio 2021-12-24 293

　　(1) Reproduction method: A healthy male rabbit weighing 2-3 kg. The surgical procedure is the same as the ferrous sulfate model. Place the intraventricular drug delivery catheter (coordinate positioning: P4, L4, R4) according to the positioning coordinates of the Sawyer rabbit brain function map, and connect and fix the recording electrodes (coordinate positioning: A8, P8, LL3, RR3mm). Tooth powder. This is exactly the same as the placement of the intraventricular drug delivery catheter and recording electrode. After a week or two, normal brain waves were used in the experiment. During the experiment, the hippocampus EEG and cortical waves were recorded first, and then 10μl (200μg/kg body weight) of sterile zinc sulfate was slowly injected through a drug delivery catheter with a microsyringe, and the injection was completed in about 5 minutes. Then, while recording brain waves and cortical waves, continuously observe the animal's general behavior, seizure time, maintenance and disappearance, seizure type, etc. changes.

　　(2) Model features After the injection of zinc sulfate into the hippocampus, the animal showed autonomous movement, cloning of the eyelids, and clonic spasm of the facial and neck muscles, extending toward the other side of the injection, and both forepaws Stretched slightly. straight. In addition, there are symptoms such as smell, licking, increased urination, increased saliva production and respiratory secretion. These symptoms are called complex local clonic seizures. Then most animals will develop secondary generalized clonic seizures. This is manifested as the correction of the neck and forelimbs or the lifting of the forelimbs. After that, the muscles all over the body developed clonic spasms. This is a typical clonic seizure. If the attack is severe, the animal will lose its balance and fall to the ground. In most animals, this generalized clonic seizure occurred within 24 hours after zinc sulfate injection, and some animals appeared within 2-5 hours. Like ferrous sulfate, its onset time is shorter and more severe, and eventually the animal cannot eat or die.

　　(3) Comparative medicine There is a zinc receptor in the NMDA receptor complex in the body. Under normal physiological conditions, zinc binds to and inhibits the receptor, thereby regulating the excitability of neurons. However, excessive free zinc ions in the brain can produce neurotoxic effects. This may be related to the activation of metabotropic glutamate receptors by zinc ions. Zinc ions cause neuronal degeneration and necrosis, leading to seizures.