Objective To establish a stable and reliable lung injury model caused by severe acute pancreatitis（SAP）in rats， which is helpful to study the acute lung injury （ALI）and acute respiratory distress syndrome （ARDS） induced by SAP.Methods Sixty Sprague-Dawley rats were randomized into ligature group （n=20）， traditional group （n=20），and sham operation group （n=20）. SAP model was established through retrograde injection of 5% taurocholic acid. After injection， the pancreatic duct of rats was ligated in ligature group， but not in traditional group. The lung damage and edema at 24 h after operaton and natural course of rats were observed.Results The ALI model of rats induced by SAP was established successfully in ligature group. The rats died of acute respiratory failure within 48 h in ligature group， the mortality was significantly higher than that in traditional group （100% vs.20%），P＜0.05. Pleural effusion occurred in four rats in ligature group， while no pleural effusion was found in rats in other two groups. The volume of ascites of rats in ligature group was （21.15±5.33） ml， which was more than that in traditional group 〔（7.75±2.66） ml〕，P＜0.05， while no ascites was found in rats in sham operation group. The level of serum amylase of rats in ligature group was （2 470.70±399.73） U/L，which was significantly higher than that in traditional group 〔（1 528.40±289.54） U/L〕 and sham operation group 〔（831.10±93.26） U/L〕，P＜0.001. The level of serum albumin of rats in ligature group was （6.90±1.66）g/L， which was significantly lower than that in traditional group 〔（13.10±0.99） g/L〕 and sham operation group 〔（16.20±0.92） g/L〕，P＜0.001.The lung wet-to-dry weight ratio （W/D） of rats in ligature group was 6.50±0.23， which was greater than that in traditional group （4.92±0.18） and sham operation group （4.61±0.16）， P＜0.001. The score of lung histopathologic of rats in ligature group was 29.25±1.07， which was significantly higher than that in traditional group （12.65±1.98） and sham operation group （0），P＜0.001. The score of pancreas histopathologic of rats in ligature group was 15.95±0.15，which was significantly higher than that in traditional group （13.75±0.66） and sham operation group （0.13±0.29），P＜0.001. Under transmission electron microscope， basement membrane of pulmonary capillary of rats in ligation group was destructive， the nuclei was dissolved， endothelial pinocytotic vesicles was functional active， and tight junctions between capillary endothelial cells were blurred and even ruptured. Moreover， tight junctions between alveolar epithelial cells were destructive. Pathological changes of lung ultrastructure of rats in ligation group were more severe than that in traditional group， while no pathological change of lung ultrastructure was observed in rats in sham operation group. Conclusions Injury process and pathogenesis of ALI or ARDS clinically caused by acute gallstone pancreatitis can be reproduced in this animal model， which is suitable to explore the related mechanisms of ALI caused by SAP and provides good animal model for the study of ALI caused by SAP.
Objective To establish chronic hindlimb ischemia model with suture-occluded method in rats， and then compare the effects of chronic hindlimb ischemia model with acute ischemia model. Methods Models of chronic hindlimb ischemia were established by using suture-occluded femoral artery method. The laser Doppler blood flow analysis and angiography were performed on day 7， 14， 28， 42， and 49 after operation， and then the rats were sacrificed after angiography， respectively， the quadriceps and gastrocnemius of contralateral and ipsilateral （surgical side） were gotten， which were tested by HE staining and α-actin immunohistochemistry staining， and then calculate arteriolar density. Results There were no lameness and limb necrosis after operation in chronic hindlimb ischemia models. Laser Doppler analysis found that chronic hindlimb ischemia models were still maintained in ischemia state on day 49 after operation compared with acute ischemic models. The resluts of HE staining showed no acute necrosis and muscle fibrosis in chronic hindlimb ischemia model group. Chronic hindlimb ischemia models after operation did not appear obvious lameness and limb necrosis. The arteriolar density of quadriceps femoris on day 7 after operation in chronic hindlimb ischemia models were less than that in acute hindlimb ischemia models （0.015 2 vs. 0.036 4）. Conclusions Compared with the commonly used acute ischemic models， the duration of arterial limb ischemia in chronic hindlimb ischemia rats， which were established by suture-occluded method， is longer and less likely to be affected by the compensatory mechanisms. So suture-occluded method can provide a new animal hindlimb ischemia model for further study of ischemia angiogenesis mechanism and treatment of severe lower extremity ischemia.
Objective To observe the dynamic histopathologic changes of acute rejection in rat orthotopic liver transplantation (OLT) model after tacrolimus discontinued and provide some prediction and evaluation data for clinical acute rejection after liver transplantation. Methods Kamada two-cuff technique was used to establish 60 rat OLT model， and male DA rats, male Lewis rats were used as donors and recipients respectively. Therapeutic amount of tacrolimus (0.05 mg/kg, twice per day, continued for 8 d, 1 d before operation and 7 d after operation, intragastric administrated) was administrated to recipients, then continuously half dose was decreased every day beginning from day 8 after operation and tacrolimus administration was stopped on day 13. Liver tissues were collected on day 7, 14, 21, and 28 after liver transplantation. Histopathologic changes and rejection activity index (RAI) of liver tissues were observed, survival time of recipients was calculated. Results Owing to protection effects of tacrolimus, liver tissues displayed no significant histopathologic changes of acute rejection in 7 d after OLT, while typical acute rejection histopathologic changes began to be observed on day 14 after OLT due to tacrolimus discontinuation. On day 14, 21, and 28, RAI were 3.7±0.9, 6.3±0.9, and 8.1±0.7 respectively. Survival time of recipients was (20.85±0.71) d with a median of 21 d. Conclusion Acute rejection could be induced in rat OLT model after tacrolimus discontinuation, and data collected from this model shows some extent of predictive value and assessment value for clinical liver acute rejection.
Objective To explore adaptive condition of preparation of animal model and afford reliable and stable model animal for further research on clinical diagnosis and treatment of cavernous transformation of portal vein (CTPV) by establishment of animal model by partial portal vein stenosis. Methods According to different straight blunttip needles used, 80 healthy Sprague-Dawley rats were randomly averagely divided into 4 groups: sham operation group, gauge 19 (19G) group, gauge 21 (21G) group and gauge 23 (23G) group. Six weeks after model making, pressure measurement and angiography of portal vein and pathological examination of portal vein and its surrounding tissues were used to evaluate portal hypertension and CTPV. Results Six weeks after model making no rat died in sham operation group, while the numbers of died rats in 19G group, 21G group and 23G group were 2, 4 and 16, respectively. No portal hypertension was displayed in sham operation group and 19G group 6 weeks after model making. Portography showed that the portal vein seemed smooth without variceal and dilatation in sham operation group and 19G group. Pathological examination demonstrated that the portal vein walls were not enlarged, endothelial cells were smooth. The smooth muscles of middle membrane were not thickened and adventitia was intact. Portal pressure increased and CTPV formed in 21G group and 23G group 6 weeks after model making. Portography showed that collateral circulation formed around portal vein in 21G group and 23G group. The vessel lumens with different size and irregular shapes were displayed by pathological examination. Within the narrow fibrous septum between there were the lumens the fat cells, scattered lymphocytes and mast cells, etc. The portal vein walls were enlarged notably, endothelial cells were damaged, the smooth muscle of middle membrane were thickened, thrombosis were formed. Conclusion Establishment of CTPV animal models by partial portal vein stenosis is a reliable method. 21G blund-tip needles fits well in the preparation of CTPV, which is reliable and stable with lower mortality.
Objective To establish the model of hepatic VX2 tumor in rabbits and to offer the experimental evidences for the application of the model. Methods The hepatoma model was reproduced with VX2 cell lines in rabbits. The method to reproduce the model was improved. The changes of liver function (ALT, AST and TB) were determined at a different phase. Tumor’s growth and metastases, pathological changes, images and spontaneous survival time of the animal were observed. Results The tumors could grow up to 1.5-2.0 cm in diameter in 3 weeks after implanting. The successful rate of implantation was 100%. Nodular enhanced echo was found in the liver by color ultrasound. CT scans showed the low density foci in liver, while enhanced CT scans demonstrated asymmetrical intensification in the foci. Macroscopic observation showed that the tumors were grayish white in color and felt harder, necrotic foci was present in the center of tumor. Observation with light microscope showed that the tumor cells’ nucleoplasm proportion was great, tumor cells arranged irregularly, and the tumors displayed invasive growth and no obvious envelope around them. Animals’ spontaneous survival time was 40-53 days. The cause for their death was multiple system organ failure. Conclusion In pathological morphology, pathological process and prognosis, the hepaticVX2 tumors in rabbits are similar to human hepatocarcinoma. It has such characteristics as easy reproduction, short growth period, high success rate, high stability and so on. The model is an ideal hepatoma model in animals.
【Abstract】Objective To establish and assess the rat model of postoperative fatigue syndrome (POFS). Methods The rat model of POFS was developed by the partial resection of the liver. The behavioral changes prior and post to operation, the disorder of nutritive intake after operation, stress reaction (pathological changes of mucous membrane in small intestine) and the hepatic albumin gene expression were observed. Results Low body temperature, lower sensitivity and reactivity were found. The serum levels of the iron, total protein, albumin, globulin and so on as the indexes of nutrition obviously dropped. The injury of the mucous membrane resulted from the stress reaction after the resection of the liver. The gene expression of the albumin decreased in the model group.Conclusion The experimental rat model of POFS by partial resection of the liver can be used for the investigation of POFS.
ObjectiveTo study the feasibility of the establishment of transplantated hepatic cancer models in SD rats. MethodsThe male weaning SD rats were inoculated and transgenerated from the celiar transplantation tumor rats (W2562k) by intraperitoneal injection of abdominal fluid of tumor cells, another weaningSD rats were prepared for the models of solid tumor by subcutaneous inoculation of the abdominal fluid of tumor cells. The solid tumors were cut to pieces of 0.2 cm×0.2 cm×0.3 cm,which were implanted into the liver of the adult male SD rats, and the transplantation hepative tumor models were established. After 7 days, the volume and weight of tumor mass was measured. ResultsThe successful rate of model was 100% (82/82), the natural extinctive rate was 0 (0/82), the successful rate of inoculation was 100% (15/15). ConclusionSD rats are economical, the successful rate of model was high, the natural extinctive low, so the SD rats are ideal selection in establishing transplantation liver cancer model.
ObjectiveTo provide the reliable model in the rat for the study of liver transplantation.MethodsA surgical experience with one hundred and fifty orthotopic liver transplants in rats was reviewed,meanwhile a simple method with biliary extradrainage as well as bile collection was introduced.Results The operative successful rate was 93.8%（91/97）,the survival rate after one week was 85.9%(55/64),the recipient underwent an anhepatic period of 19 min,the operative time of donor and recipient were 37 min and 56 min,respectively.ConclusionThe result indicates that the model is reliable in the study of liver transplantation.The hard work and meticulous surgical performance are the key to successful operation.
【Abstract】Objective To introduce three methods of creating the animal model of bone metastasis from breast cancer and the advances in the application of these models. Methods The related literatures were collected and reviewed.Results In summary, breast cancer cells injected through left ventricles was commonly used. Breast cancer cells injected into medullary cavity of shaft of femur was simple and effective, but it was very different from the real condition of bone metastasis of patients. The development of animal model created by surgical orthotopic implantation gives the researchs an ideal instrument similar with the condition of patients to research the mechanism of bone metastasis and the treatment. Conclusion Each animal model of bone metastasis from breast cancer has itself usefulness. Our destination is to create the real model of bone metastasis from breast cancer that is very similar with the patients.
【Abstract】Objective To investigate the effect of ischemia on the treatment of advanced body and tail carcinoma of pancreas. Methods In operation the proximal spleen artery was ligated, a chemotherapy pump was installed to connect the distal spleenic artery and urea solution (40%) was injected through the device during and after operation. The pathology and pathophysiology change in dogs were observed. Results All the eight dogs studied were alive after operation, no serious complication appeared, pancreatic cells were replaced by fibrosis. Conclusion Infusion of 40% urea solution is a safe and effective ischemic method, it can lead to all sorts of pancreatic cell necrosis and fibrosis. It may be a good madality in the treatment of advanced pancreatic carcinoma.