疾病动物模型,快速心房起搏房颤模型 z-bio 2021-03-09 266

　　[Modeling mechanism] The rapid atrial pacing atrial fibrillation model is currently the most studied and most widely used animal model of chronic atrial fibrillation. This mechanism is related to electrical and structural remodeling caused by rapid atrial pacing. Various animal models are shown without exception. The reduction of effective atrial refractory period (ERP), the reduction of frequency adaptability, the obvious increase of atrial diameter and volume, and the increase of anisotropy promote multi-wave reentry. .. The main ionic mechanism is to down-regulate the L-type calcium current IC, L, the instantaneous outward potassium current Ito and the delayed rectifier potassium current IK.

　　[How to make a model]

　　(1) Dog: Use healthy adult male or female dogs weighing 16 to 30 kg. After intravenous anesthesia with pentobarbital sodium (30 mg/kg), use isoflurane (2 mg/kg) and intravenous chloralose (0.3-0.4 mg/kg) or acepromazine (0.3-0.4 mg/kg) ) Maintain general anesthesia. Maintain general anesthesia by inhaling% halothane, 2L/min nitrous oxide, 1L/min oxygen and 2L/min medical gas. Under the guidance of the X-ray equipment, the 6F quadrupole reed was sent from the femoral vein to the right atrium to determine the atrial pacing threshold. Give the atria 400-800 times/min, which is 2-4 times the pulse width of 2 milliseconds, and the threshold voltage S1S1 (300 milliseconds) or S1S2 (S1S1/S1S2300ms/200 milliseconds, the step size is reduced by 5 milliseconds). The program stimulates atrial fibrillation scan) .

　　(2) Goat: Use goats weighing 15-65 kg. Intravenous injection of thiopental sodium (10 mg/kg), inhalation of halothane (1%-2%), 1:2 oxygen: nitrous oxide mixed gas to maintain general anesthesia. Open the left chest, cut the heart bag, place the electrodes on the left and right atrioventricular epithelial walls of the goat and Backman bundle, suture the chest wall, and connect the electrodes to the external defibrillator, connect and stimulate multiple sites at 50 Hz at the same time Frequency, 1 ms duration and 20 ms interval burst stimulation, and four times the defibrillation threshold intensity. Stop stimulation when atrial defibrillation occurs, and stop stimulation when atrial defibrillation occurs. If it changes to sinus rhythm, the stimulation continues.

　　(3) Other animals: This model can be successfully replicated in mice, rats, rabbits, etc. After the animal is anesthetized, the electrode is placed in the right atrium and high-frequency stimulation is performed. Most animals can induce atria. Fibrotic. Seizures.

　　[Model Features] Acute radiofrequency stimulation can induce atrial fibrillation within 10 seconds to 30 minutes, while chronic radiofrequency stimulation lasting 6-8 weeks can reproduce spontaneous atrial fibrillation.

　　[Model Evaluation and Application] The animal model of atrial fibrillation established by rapid right atrial pacing has a high success rate, high reproducibility, and a long maintenance time of atrial fibrillation, leading to non-valvular diseases. , Myocardial remodeling, molecular biological changes and other clinical studies can also be used to study tachycardia cardiomyopathy and partial heart failure. However, this method requires attention to control the ventricular rate.