动物模式,视神经牵拉伤 z-bo 2020-08-08 807

　　(1) Reproduction method The guinea pig weighing about 700g is injected intraperitoneally with pentobarbital sodium anesthetized at a dose of 30mg/kg body weight, and then incise the outer abutment under an operating microscope, cut the corneal edge 360°, and free the conjunctiva and extraocular muscles , Expose the optic nerve and separate it from the surrounding tissues. Take a sterile sling, cut a 5mm long crack at the midpoint, place it on the eyeball, fix it with a silk thread, and make the optic nerve pass backward through the crack. The guinea pig is fixed on the stereotaxic frame, and the head support frame is adjusted to make the axis of the optic canal consistent with the pulling direction. The two ends of the sterile sling fixed on the ball are connected to the cylinder of the pulling device with silk threads. A pulse generator sends out a constant voltage to drive the piston to move, which is transmitted to the pulling device through the pulley system. The transmission path is cylinder 1. Sling an optic nerve, so that the optic nerve is pulled until it causes an optic nerve traction.

　　(2) The characteristics of the model can cause optic nerve traction injury. The methods can be divided into traction consistent with the axis of the optic canal and traction hanging from the axis of the optic canal. The former can definitely cause diffuse axonal injury, and the latter is For example, cutting injuries caused by optic canal fractures, both can more accurately quantify the degree of injury. However, experimental research with this model method can obtain better clinical significance.

　　(3) Comparative medicine The mechanism of optic nerve injury is very complicated, including primary optic nerve and vasculature injury such as shearing, squeezing, and stretching, as well as secondary ischemic injury caused by optic nerve swelling in the optic canal. Most animal models lack the optic nerve tube, and can only simulate one or two injury states, but cannot fully simulate the optic nerve injury state. The ideal optic nerve injury animal model as the evaluation principle of the human disease animal model should meet the following requirements: ①The injury equipment is simple, easy to operate, few surgical steps, small trauma to experimental animals, and low animal mortality. ②The injury rate is high, which can cause exact optic nerve damage, while avoiding damage to the central retinal artery and choroidal capillary layer, and can accurately quantify the degree of damage. ③The injury state is as close as possible to the clinical injury state, so that the experimental research has clinical significance.