不同压力的作用形式对压疮缺血再灌注损伤的实验研究

发布时间：2018-06-22 04:56

本文选题：压疮 + 大鼠　；参考：《山西医科大学》2012年硕士论文

【摘要】：目的通过建立SD大鼠的压疮动物模型，比较不同压力的作用形式（垂直压力、摩擦力和剪切力）对大鼠压疮皮肤及肌肉组织在肉眼和病理学方面的变化；并比较血清超氧化物歧化酶(SOD)的活性、丙二醛(MDA)和一氧化氮(NO)含量的变化，为其纳入压疮危险因素评估表并给予相应分值提供理论依据。方法32只SD大鼠雌雄不限，麻醉后仰卧于倒置的玻璃注射器加压装置。此装置用止血带将空心玻璃管与玻璃注射器的空筒相连。在装置内加水，由水柱产生的压力通过注射器的活塞可作用于大鼠后肢膝关节骨隆突处的皮肤组织。此处皮肤组织即为受压部位。通过计算受压部位的面积和加压的重量，使此处皮肤组织受到9kPa的压强。将大鼠随机分为4组：对照组（A组），大鼠仰卧于鼠板上，未施加任何压力7.5小时后处死；垂直压力组（B组），给予受压部位垂直压力2h再放松0.5h；摩擦力组（C组），给予受压部位垂直压力2h并在2h末用棉布在此处往返摩擦，摩擦距离为1cm，之后放松0.5h；剪切力组（D组），大鼠后肢受压部位用胶贴向肢体远端牵拉0.3～0.5cm，同时压迫此处皮肤组织2h再放松0.5h；各实验组均给予三个缺血(压迫2h)-再灌注（放松0.5h）循环后处死。肉眼观察大鼠受压部位皮肤完整性和颜色变化，在光镜下观察受压部位的表皮及肌肉组织的病理学变化，并测定血清中超氧化物歧化酶(SOD)的活性、丙二醛(MDA)和一氧化氮(NO)的含量。结果1、肉眼观察：A组大鼠受压部位颜色未见明显改变且皮肤组织完整；B组大鼠皮肤完整，但与实验前相比皮肤转为了紫红色；C组大鼠受摩擦处皮肤发红且有散在、针尖大小的点状破损；D组大鼠皮肤组织较完整，但与实验前相比呈现暗红色。 2、光镜观察：A组大鼠上皮组织结构清楚，为复层鳞状上皮。肌纤维排列紧密有序，横纹清晰，呈编织状排列。B组大鼠复层鳞状上皮相对于A组变薄，结构不清，细胞层次减少。肌纤维水肿明显，间质增宽，横纹模糊。C组大鼠复层鳞状上皮较B组变薄，甚至角化，结构不清。肌纤维水肿明显，间质增宽，横纹断裂。D组上皮组织较薄，，结构不清。肌纤维较B组水肿明显，较疏松，横纹断裂较多，间质水肿增宽。各实验组受压部位肉眼及光镜观察均出现损伤，其中剪切力组肌肉损伤比垂直压力组更明显；摩擦力组表皮损伤比垂直压力组更明显。 3、生化指标检测：各实验组与对照组比较：SOD活性、MDA和NO含量均有统计学意义（P0.01）。各压迫缓解组之间比较也均有统计学意义。其中，摩擦力组与垂直压力组比较：SOD活性下降（P0.01）、NO含量下降（P0.05）、MDA含量增加（P0.05）。剪切力组与垂直压力组比较：SOD活性和NO含量明显下降（P0.01）,MDA含量明显增加（P0.01）。剪切力组与摩擦力组比较：SOD活性下降（P0.05），NO含量下降（P0.01），MDA含量增加（P0.05）。结论1、缺血再灌注引起了组织细胞损伤而导致压疮。 2、剪切力主要造成了深部组织的损伤。 3、摩擦力主要造成了表皮组织的损伤。 4、垂直压力、摩擦力和剪切力可以纳入压疮危险因素评估表且分值依次递增。
[Abstract]:Objective to establish a model of pressure ulcers in SD rats and to compare the changes in the skin and muscle tissue of pressure sore in rats with different forms of pressure (vertical pressure, friction force and shear force), and to compare the activity of serum superoxide dismutase (SOD), the content of malondialdehyde (MDA) and nitric oxide (NO), and the changes of the content of malondialdehyde (MDA) and nitric oxide (NO). The risk factors of pressure ulcer were assessed and the corresponding scores were provided.
Methods 32 SD rats and male and female rats were placed on the back of the inverted glass syringe pressure device. The device used a tourniquet to connect the hollow glass tube to the empty tube of the glass syringe. In the device, water was added to the device, and the pressure produced by the water column could be used in the skin tissue of the knee joint of the hind limbs of the rat by the piston of the syringe. The skin tissue is the compressed part. By calculating the area of the compressed part and the weight of the pressure, the skin tissue is subjected to the pressure of 9kPa.
The rats were randomly divided into 4 groups: the control group (group A), the rats were lying on the rat board with no pressure for 7.5 hours. The vertical pressure group (group B) gave the vertical pressure of the compression site 2H and then relaxed 0.5h; the friction force group (group C) gave the vertical pressure of the compression position 2H and then rubbed with cotton cloth here at the end of 2h, and the friction distance was 1cm. In the shear group (group D), the compression part of the hind limbs of the rats was pulled 0.3 to 0.5cm by glue to the distal extremities, and the skin tissue was compressed to relax 0.5h at the same time, and 0.5h was relaxed in the skin tissue. All the experimental groups were given three ischemic (oppressed 2H) reperfusion (relaxation 0.5h) and then executed after the circulation.
The skin integrity and color change of the pressed part of the rat were observed by the naked eye. The pathological changes of the epidermis and muscle tissue in the compressed part were observed under the light microscope, and the activity of superoxide dismutase (SOD) in the serum, the content of malondialdehyde (MDA) and nitric oxide (NO) in the serum were measured.
Results 1, naked eye observation: the skin color of group A rats was not obviously changed and the skin tissue was intact. The skin of group B rats was complete, but the skin turned to purplish red compared with that before the experiment; the skin of group C was red and scattered, the point shape of the needle tip was damaged; the skin tissue of group D rats was more complete, but compared with that before the experiment. It's dark red.
2, light microscope observation: the epithelial tissue structure of group A rats was clear, it was complex layer squamous epithelium. The muscle fibers arranged closely and orderly, the transverse lines were clear, and the.B group of rats were thinner than the A group. The structure was not clear, the cell level decreased. The muscle fiber edema was obvious, the interstitium was widened, and the cross layer blurred.C group was compared with the B group. Thinning, even diagonalization, the structure is not clear. The muscle fiber edema is obvious, the interstitium is widened. The epithelial tissue of the.D group is thinner and the structure is not clear. The muscle fiber is more obvious than the B group, looser, more transverse fracture and wider interstitial edema.
All the experimental groups were injured by naked eye and light microscope, and the muscle damage in the shear group was more obvious than that in the vertical pressure group, and the skin damage in the friction group was more obvious than that in the vertical pressure group.
3, biochemical index test: compared with the control group, SOD activity, MDA and NO contents in each experimental group were statistically significant (P0.01).
SOD activity decreased (P0.01), NO content decreased (P0.05) and MDA content increased (P0.05). The shear force group and the vertical pressure group were compared with the vertical pressure group: SOD activity and NO content decreased significantly (P0.01), MDA content increased significantly (P0.01). Shear force group and friction. Compared with the control group, SOD activity decreased (P0.05), NO content decreased (P0.01), and MDA content increased (P0.05).
Conclusion 1. Ischemia and reperfusion cause tissue cell injury and cause pressure ulcers.
2, the shear force mainly causes the damage of the deep tissue.
3, the friction force mainly causes the damage of the epidermis.
4, vertical pressure, friction and shear force can be included in the risk factors for pressure ulcer risk assessment.
【学位授予单位】：山西医科大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R363

【参考文献】