动物造模,药效评价,应激性十二指肠溃疡 z-bio 2024-08-21 351

　　(1) Method of replication: Adult rats were fasted without water for 16 hours, anesthetized with intraperitoneal injection of pentobarbital sodium, and fixed. Then, an electric pusher was used to push the hairs slightly larger than the intended burn area. Dip a gauze ball in a warm 20% sodium sulfide solution and gently pat evenly on the depilated area. Wait for the hair to melt, rinse the depilatory agent with warm water, remove the water with gauze, dry the depilated skin with a hair dryer, and cover the area around the skin with a damp cloth. Evenly apply 3% solidified gasoline at a weight ratio of 0.01ml/kg onto the surface of the skin to be burned, and ignite and burn for 30 seconds in a stable airflow environment. Among them, the method for preparing 3% solidified gasoline is to accurately weigh 3g of solidified gasoline powder, add gasoline to 100ml, place it in a grinding bottle and stir thoroughly until the oil powder is evenly mixed into a gel. Immediately after injury and at different time points thereafter, anesthesia is performed for laparotomy, fully exposing the stomach and duodenum, separating the omentum and part of the mesentery, and cutting along the greater curvature of the stomach to the duodenum. The opened duodenum is rinsed with 4 ℃ physiological saline to observe the damage to the duodenal mucosal surface with the naked eye, and some tissues are taken for histological light and electron microscopy examination.

　　(2) After burning, the duodenal mucosa surface of the model animal developed ulcers, local erosions, and necrosis. Under electron microscopy, it can be seen that the entire volume of the duodenal villi is enlarged, thick, and long, with blurred surface folds and layers, rough grooves, disordered arrangement, and partial detachment of the top tissue of the villi. Some surfaces have dotted or strip-shaped defects. 2-5 hours after injury, intestinal villi edema continued to exist, but the extent of damage expanded and worsened. After 8 hours of injury, there is still edema in the villi, and most of the villi have varying degrees and areas of necrosis, with some villi splitting into two halves. 24 hours after injury, the degree of damage to the villous structure is extremely severe, reaching its peak. Some villi split into several pieces, segments, and several necrotic villi fused together to form a necrotic lesion, which is either honeycomb shaped or hollow, and has a substance similar to soybean residue accumulation. 72 hours after injury, the edema basically disappeared, but the surface structure remained disordered, and the necrotic foci of villi still existed.

　　(3) When comparing medical burns, various factors can lead to a strong stress response in the body. The increased excitability of the sympathetic nervous system and adrenal medulla can cause strong constriction of mucosal blood vessels, reduced local blood flow, and decreased mucosal barrier function, leading to stress-induced duodenal ulcers. This model can not only cause damage to intestinal villi, but also induce ulcers in the gastric mucosa, which is determined by a common pathophysiological basis. Generally speaking, the overall incidence, timing, and severity of duodenal mucosal lesions caused by burns are more sensitive and severe compared to the damage to gastric mucosa. This model is suitable as an animal model for studying the damage to gastrointestinal mucosa caused by severe burns and its prevention and treatment measures.