动物造模,药效评价,脑动静脉畸形 z-bio 2024-09-20 326

　　The previous animal models of cerebral arteriovenous malformations were arteriovenous fistulas without a true malformation mass structure. Massoud et al. established for the first time in 1994 an animal model of cerebral arteriovenous malformation containing a malformed mass structure using surgical vascular anastomosis and endovascular occlusion techniques in pigs.

　　(1) The replication method uses pigs aged 3-4 months and weighing 20-40kg, regardless of gender. Intramuscular injection of ketamine anesthesia at a dose of 100mg/kg body weight, followed by vascular angiography via femoral artery catheterization. Make a lateral midline incision about 10cm downwards on the right mandible, separating and exposing the right common carotid artery and internal or external jugular vein. Perform end-to-end anastomosis of the right common carotid artery and internal or external jugular vein using 9-0 suture thread, ligate the residual ends of the proximal end of the common carotid artery and the distal end of the vein, and simultaneously ligate the right external carotid artery. Thus, an AVM model was formed with the left ascending pharyngeal artery as the blood supply artery, the skull base microvascular network as the malformation group, and the right ascending pharyngeal artery to the right common carotid artery through the anastomosis opening to the right external jugular vein, forming a drainage vein with the malformation group.

　　Subsequently, left common carotid artery and ascending pharyngeal artery angiography were performed immediately to confirm that blood flowed along the left ascending pharyngeal artery, skull base microvascular network, and diverted to the right internal or external jugular vein through the right ascending pharyngeal artery, right common carotid artery, and carotid arteriovenous anastomosis, displaying imaging features consistent with AVM.

　　(2) The model features pigs and some cloven hoofed animals, such as cows, sheep, etc., with a microvascular network wrapped by the cavernous sinus at the base of the skull. The microvascular network at the base of the pig skull is H-shaped, with a size of about 2cm × 3.5cm × 0.2cm, resembling a deformed mass of human AVM on vascular imaging. The average diameter of blood vessels in the microvascular network is 154 μ m, and these microvessels have clear inner elastic membranes and a distinct middle muscle layer (with an average thickness of 36 μ m), with sparse connective tissue between microvessels. The microvascular network of pig skull base is a good tissue structure for creating abnormal masses in animal models of cerebral AVM.

　　(3) The average arterial pressure in the ascending pharyngeal artery of normal pigs in comparative medicine is 77mmHg. After establishing an AVM model, the pressure gradient difference between the average pressure in the left ascending pharyngeal artery (i.e. AVM type feeding artery) and the average pressure in the right ascending pharyngeal artery (i.e. model draining vein) is similar to the average pressure in the right common carotid artery (part of the model draining vein). When using particle emboli, such as human collagen particles, for embolization through the left pharyngeal artery, the internal pressure gradually increases, which is consistent with the changes in the internal pressure of the blood supply artery during cerebral AVM embolization. The model has good simulation ability for human brain AVM.