Elastase-induced Emphysema In Pig Animal Model

Objective: To make an animal model of heterogeneous emphysema by localized Porcine pancreatic elastase instillation, it provided us a useful animol model to better understanding of chronic obstructive pulmonary disease (COPD) of the inducing factors, pathogenesis, pathology, treatment, and treatment.Method: From February 1, 2010 to March 3, 2010 on the Experimental Animal Center of Jilin University,we use 12 small-scale pigs to do our experiments.the small pigs were divided into two groups, experimental group 9 and the normal group 3, respectively before the experiment we do lung CT and pulmonary function tests for all the pigs, and then we instill elastase into the tracheal of the experimental group pig`s left lung lower lobe through the bronchoscope, the normal group pig was instilled as described above the same amount of saline droplets ,when we instilled elastase five times,we waited another one week, and then do lung CT, lung function, and histopathological examination.Result: when we instilled the elastase into one pig in Experimental group in the fourth week, it caused it pneumothorax and death due to positive pressure ventilation in the lung bullae rupture,. The remaining eight pigs was done the lung CT scan and showed: left lower lobe bulla in five cases, emphysema-like changes in the remaining three cases.in the nomal group there is no emphysema-like changes.12 cases of animals in the lung function tests were performed before the experiment and the experimental group and the nomal group TLC, FRC, FRC / TLC%, VT, BR contrast, showed no difference. do lung function test after the experiment again, the experimental group and the nomal group TLC, FRC, FRC / TLC%, VT, BR contrast, the results show quite different.eight pigs before the animal model of elastase induced emphysema was in pulmonary function tests, after five weeks injected elastase, we waited another one week,then did pulmonary function tests, before and after testing compared TLC, FRC, FRC / TLC%, VT was significantly increased, BR speed. And compared before and after test results showed statistically significant differences.after five weeks injected elastase, we waited another one week,then we killed a pig for pathological examination in experiment group, in the normal group also killed a pig as a comparison. Light microscope after HE staining pathological, and do the image comparison shows: the nomal group of small pig alveolar, vascular, bronchial were normal, normal alveolar size and shape of the rules, sometimes breaking, consider it is the physical factors. Experimental mini-pig lung alveolar ducts, alveolar sacs, alveoli, bronchioles, compared with the nomal group were significantly expanded alveolar wall was thin and broken in several places, merging into larger adjacent pulmonary alveoli, elastic fiber damaged.Discussion: In this paper, from February 1, 2010 to March 3, 2010, on the Experimental Animal Center of Jilin University, we use small pigs to experiment to establish a large animal model of emphysema, and successfully established a large animal model of emphysema. The following conclusion:(1) we used elastase to successfully establish animal model of emphysema pigs to make up the domestic blank in this respect.it proved the feasibility that we used the pig to establish the model of emphysema, but it also provided us a useful basis after the establishment of emphysema in animal models of pig.(2) Anesthesia on the pig, in this experiment we used ketamine and propofol anesthesia method to obtain the ideal anesthetic effect. That is on the pig under general anesthesia, we known that more than one kind of anesthetic could get better effect than the single drug .(3) Entire experiment lasted one month, shorter, more convenient operation, no personnel was injured, and all the checks before and after the experiment showed that we have successfully established large animal model of emphysema, help us to know emphysema more including predisposing factors, pathogenesis, pathology, medical observation of drug therapy and surgical treatment of emphysema LVRS indications of choice, the choice of surgical excision of the lesions, the assessment of treatment.(4) Successfully established model can provide us a reliable experimental animal model to help us more for the next step of fiberoptic bronchoscopy lung volume reduction surgery .