Objective To establish the model of pancreatoduodenal allotransplantation in pigs with enteric drainage (ED) and portal venous drainage (PVD). Methods Forty-six hybrid landraces were divided into two groups (donor and recipient groups) randomly, for pancreatoduodenal allotransplantation. Donors were perfused via abdomial aorta without clamping the portal venous outflow with UW solution after heparinization. Whole pancreatoduodenal graft was arvested with segments of abdomial aorta and portal vein and shaped under cold UW solution. Then, the end-to-end nastomosis was performed with the donor iliac artery bifurcation “Y” graft to the recipient superior mesenteric arteries and celiac artery. Furthermore, type Ⅰdiabete model was made by removal of the recipient pancreas. The venous anastomosis was reconstructed between the donor portal vein and the recipient superior mesenteric vein. Meanwhile, the end-to-side anastomosis was performed with the donor common iliac artery bifurcation “Y” graft to the recipient abdomial aorta and the side-to-side intestinal anastomosis was performed between the donor duodenum and the recipient jejunum. External jugular vein was intubated for transfusion. The levels of blood glucose， insulin and glucagon in blood were measured before and during the operation and 1， 3， 5， 7 d after operation. Results Twenty-three cases of pancreatoduodenal allotranplantations were performed on pigs. One died from complication of anesthesia. Success rate of operation was 95.7％.Complications of operation happened in 2 cases in which one was phlebothrombosis, incidence 4.5％and the other was duodenojejunal anastomotic leak, incidence 4.5％. The level of blood glucose increased within 30 min and recovered on the 2nd day after removal of pancreas. The levels of insulin and glucagon decreased within 30 min and recovered on the 2nd day after removal of pancreas. Rejection curred at the 1st day and reached the worst level on the 9th day after transplantation without the change of insulin and glucagon in blood and clinical symptoms of rejection. Conclusion Pancreatoduodenal transplantation in pigs can treat type Ⅰ diabete. ED and PVD can keep the function of endocrine in normal. The technique of duodenal transplantation with ED and PVD may pave the way for the further development of pancreas transplantation in clinic.
ObjectiveTo observe the pathological changes in heart and lung tissues in rats with pulmonary hypertension induced by monocrotaline. MethodsTwenty-four male Sprague-Dawley rats were randomly and equally divided into an experimental group and a control group. The rats in the experimental group were intraperitoneally injected with monocrotaline to induce pulmonary hypertension, and the rats in the control group were treated with saline. All rats were fed for 3 weeks, and the general situation were observed. Then the rats were sacrificed for measurement of mean pulmonary artery pressure (mPAP), right ventricular hypertrophy index [RV/(LV+S)], changes of myocardial cells and lung vascular, calculated density of middle membrane smooth muscle cells (SMC) in medium/small pulmonary arteries accompanied with bronchi and alveoli, media thickness of pulmonary artery (PAMT), the percentage of wall thickness with outer diameter (WT%), the percentage of wall area with total area (WA%), the average diameter of myocardial cells (AD), and myocardial nuclei density (MND). ResultsCompared with the control group, the condition of rats in the experimental group were getting worse obviously.mPAP and RV/(LV+S) were both increased (both P < 0.05). The observation by light microscope revealed that obvious myocardial hypertrophy and structure disturbances, severe luminal stenosis of medium/small pulmonary arteries, medial thickening, infiltration of inflammatory cell in tissue space, proliferation of unorganized collagen fibers in the experimental group. The observation by electronic microscope showed proliferation of endothelial cell with irregular nuclei, increased organelles and vacuoles in the experimental group. The differences in SMC, PAMT, WT%, WA%, AD, and MND were significant between two groups (all P < 0.05). ConclusionsThe monocrotaline can induced pulmonary hypertension and right ventricular hypertrophy. The mechanism may be related to severe stenosis or occlusion of the vessel lumen caused by plexiform proliferation of endothelial cells, proliferation of smooth muscle cells and collagen fibers, compensatory hypertrophy and hyperplasia of myocardial cells.
ObjectiveTo study the feasibility and advantages of preparing an animal model of defecation reconstruction after spinal cord injury in rats by mechanical polishing method. MethodsForty adult female Sprague Dawley rats (weighing, 250-300 g) were randomly divided into 2 groups (n=20). The lamina was opened by mechanical polishing method to expose the cauda equina in experimental group, then bilateral L5 and S1 nerve roots end-to-end anastomosis was done under 10 times microscope, and finally cauda equina between the L5 and L6 (except S1) was cut. The lamina was opened by traditional bites method in control group, and the other treatment methods were in agreement with the experimental group. The operative time, intra-operative blood loss, and situation of rats at postoperative 3 days were recorded. ResultsThe operative time of experimental group[(93.05±7.60) minutes] was significantly shorter than that in control group[(131.30±11.68) minutes] (t=12.279, P=0.000); intra-operative blood loss in experimental group[(4.33±0.46) mL] was significantly lower than that in control group[(7.36±0.58) mL] (t=18.293, P=0.000). At 3 days after operation, 18 rats (90%) survived in experimental group, and 12 rats (60%) survived in control group; difference was significant in the survival rate between 2 groups (χ2=4.800, P=0.028). ConclusionTo establish an animal model of defecation reconstruction after spinal cord injury in rats by mechanical polishing method is feasible, and it has shorter operative time, less blood loss, and lower postoperative mortality than the traditional bites method. But there is a certain learning curve and requirement to master microsurgical techniques.
ObjectiveTo understand the initiation, maturing, and resolution of thrombus by comparing the length and weight of thrombus at different time in the rat inferior vena cava (IVC) stenosis model. MethodsForty-eight female Sprague Dawley rats, weighing 180-230 g, were selected to prepare the IVC stenosis model by blocking the most of the IVC blood flow. The length and weight of IVC thrombus were measured at different time points, the histological features were observed via HE staining. ResultsBlood clots formed after 2 hours of modeling, the thrombus length and weight showed no significant difference between at 2 hours and 4 hours after modeling (P>0.05). The thrombus length and weight increased significantly at 6 hours, showing significant differences between at 2 and 4 hours and at 6, 8, 12, 24, and 48 hours (P<0.05); and from 6 to 48 hours, there was no significant difference in the thrombus length and weight (P>0.05), indicating that thrombus was stable, or maturing. Blood clots began to become smaller after 3 days when compared with ones at 48 hours (P<0.05), indicating the start of resolution at 3 days. At 7 days, the thrombus length and weight became further smaller when compared with ones at 3 days (P<0.05). The thrombus completely subsided at 21 days, the IVC recanalized. HE staining showed that thrombus formed after 2 hours of modeling; from 6 to 48 hours, the lumen became hyperemia, and the inflammatory cells, especially neutrophils, could be found. The organization of thrombus could be observed at 3 days and 7 days; thrombus gradually vanished at 21 days. ConclusionThe time of thrombus initiation, maturing stage, and resolution stage is 6 hours, 6 to 48 hours, and 3 to 21 days after modeling, respectively.
Objective To explore improvement of orthotopic liver transplantation model in rhesus monkey. Methods Healthy rhesus monkeys were chosen to perform orthotopic liver transplantation for 10 cases. The model was established by drawing on a variety of animal model methods, and the portal vein cuff method was used to establish stable model of orthotopic liver transplantation in rhesus monkeys. Results Ten orthotopic liver transplantation models in rhesus were performed, and the achievement ratio of operation was 10/10. The time of donor hepatectomy and donor preparation was (20±5) min and (30±7) min, respectively. The operation time of recipient and anhepatic phase were (180±35) min and (17±4) min, respectively. After 24 h of operation 9 cases survived, one case died of intra-abdominal hemorrhage after 9 h of operation. After 72 h of operation 8 cases survived, and one case died of upper gastrointestinal bleeding after 38 h of operation. After one week of operation 5 cases survived, and 3 cases died of rejection after 9, 11, and 11 d of operation, respectively. The longest survival time was 32 d, but all of them also died of rejection. No portal vein thrombosis and biliary complications were found in all recipients.Conclusion The improved rhesus monkey model of orthotopic liver transplantation is easy to perform with high achievement ratio of operation. It is an ideal animal model for pre-clinical studies of liver transplantation.
Objective To investigate the feasibility of establishing an anterior cruciate ligament (ACL) reconstruction model using hamstring tendon autograft in cynomolgus monkeys. Methods Twelve healthy adult male cynomolgus monkeys, weighing 8-13 kg, were randomly divided into two groups (n=6). In the experimental group, the ACL reconstruction model of the right lower limb was prepared by using a single bundle of hamstring tendon, and the ACL of the right lower limb was only cut off in the control group. The survival of animals in the two groups was observed after operation. Before operation and at 3, 6, and 12 months after operation, the knee range of motion, thigh circumference, and calf circumference of the two groups were measured; the anterior tibial translation D-value (ATTD) was measured by Ligs joint ligament digital body examination instrument under the loads of 13-20 N, respectively. At the same time, the experimental group underwent MRI examination to observe the graft morphology and the signal/ noise quotient (SNQ) was caculated. Results All animals survived to the end of the experiment. In the experimental group, the knee range of motion, thigh circumference, and calf circumference decreased first and then gradually increased after operation; the above indexes were significantly lower at 3 and 6 months after operation than before operation (P<0.05), and no significant difference was found between pre-operation and 12 months after operation (P>0.05). In the control group, there was no significant change in knee range of motion after operation, showing no significant difference between pre- and post-operation (P>0.05), but the thigh circumference and calf circumference gradually significantly decreased with time (P<0.05), and the difference was significant when compared with those before operation (P<0.05). At 6 and 12 months after operation, the thigh circumference and calf circumference were significantly larger in the experimental group than in the control group (P<0.05). At 3 and 6 months after operation, the knee range of motion was significantly smaller in the experimental group than in the control group (P<0.05). Under the loading condition of 13-20 N, the ATTD in the experimental group increased first and then decreased after operation; and the ATTD significantly increased at 3, 6 months after operation when compared with the value before operation (P<0.05). But there was no significant difference between the pre-operation and 12 months after operation (P>0.05). There was no significant change in ATTD in the control group at 3, 6, and 12 months after operation (P>0.05), and which were significantly higher than those before operation (P<0.05). At each time point after operation, the ATTD was significantly smaller in the experimental group than in the control group under the same load (P<0.05). The MRI examination of the experimental group showed that the ACL boundary gradually became clear after reconstruction and was covered by the synovial membrane. The SNQ at each time point after operation was significantly higher than that before operation, but gradually decreased with time, and the differences between time points were significant (P<0.05). Conclusion The ACL reconstruction model in cynomolgus monkey with autogenous hamstring tendon transplantation was successfully established.
ObjectiveTo establish pig abdomen bullet wound model in seawater immersion condition and to analyze injury characteristics. MethodsTwenty Xishuangbanna pigs were randomly divided into seawater immersion group and control group,with 10 in each group.The left lower quadrant anti McBurney point of the pig semi-floating in the seawater was shot by using domestic 81-1 assault rifle at the distance of 10 meters,which were salvaged out of seawater at 60 minutes after injury in the seawater immersion group.The pigs in the control group were treated same as the seawater immersion group except seawater immersion.The mean arterial pressure (MAP),rectal temperature (RT),heart rate (HR),respiratory (R),white blood cell count (WBC),and C-reactive protein (CRP) were tested at 1 h,4 h,8 h after injury.The death of pig was observed. ResultsThe pig abdomen bullet wound models in the seawater immersion condition were successfully established.① Compared with the control group,the MAP and RT were significantly decreased at 1 h,4 h,8 h after injury,the HR or the R was significantly decreased at 4 h or 8 h after injury respectively in the seawater immersion group.② Compared with the normal value,the WBC obviously rose at 4 h and 8 h after injury,the CRP obviously rose at 1 h,4 h,and 8 h after injury in both two groups.Compared with the control group,the WBCs were significantly increased at 4 h and 8 h after injury (P<0.05),the CRPs were significantly increased at 1 h,4 h,and 8 h after injury (P<0.05) in the seawater immersion group.③ The mortality in the seawater immersion group (50%) was significantly higher than that in the control group (20%,P<0.05). ConclusionThe injury is more serious,the infection time is earlier,and the infection degree is aggravated,the mortality rate is higher for pig abdomen bullet wound model in seawater immersion condition.
The macula is a critical anatomical structure for primates to acquire high-resolution spatial and color vision, with macula lesions posing a significant threat to patients' visual function and quality of life. Non-human primate (NHP) are the only mammals with a macular structure that is closest to that of humans, thus offering substantial value in the study of macular diseases. Currently, various methods, including spontaneous occurrence, gene editing, drug-induced, light-induced, and mechanical injury, can be employed to screen and establish NHP models for investigating conditions such as oculocutaneous albinism, achromatopsia, retinitis pigmentosa, age-related macular degeneration, and certain rare ocular syndromes. When constructing NHP models, due consideration should be given to other animal models to facilitate complementary research across different model systems. Additionally, leveraging the advantages of NHP and establishing genetically controlled NHP strains is a goal to strive for to achieve sustainable utilization of these resources in research.
ObjectiveTo establish a rat model of diabetic microangiopathopathy and simulate the biochemical and pathological changes of diabetic retinal and renal microangiopathopathy. MethodsForty healthy male Sprague-Dawley rats were randomly divided into blank group and model group (10 and 30 rats, respectively). After the rats in blank group and model group were fed ordinary diet and high-fat and high-sugar diet for 5 weeks, respectively, the rats in model group were injected with 1% streptozotocin (STZ) through the abdominal cavity at the dose of 35 mg/kg to establish a type 2 diabetes model. After modeling, the rats were continuously fed until the 10th week (4 weeks after modeling), the general conditions of the rats were observed, and samples were collected for follow-up experiments. Serum creatinine (CREA), triglyceride (TG), total cholesterol (TC), high density lipoprotein (HDL-C), low density lipoprotein (LDL-C), microalbuminuria, urinary creatinine (UCr) and urine sugar were detected. Calculate the kidney index and microalbumin/urinary creatinine ratio (UACR). Optical coherence tomography angiography (OCTA) was used to observe the vascular changes and non-perfusion area of retinal superficial capillary plexus. The morphological and structural changes of kidney and retina were observed by hematoxylin-eosin and periodate Scheff staining. The expression of nerve fibers and nucleus of Müller cells in rat retina was observed by immunofluorescence staining. Ultrastructural results of retina were observed by transmission electron microscope. Independent sample t test was used for comparison between groups. ResultsFour weeks after modeling, compared with blank group, the body weight of rats in model group was significantly decreased, and random glucose was significantly increased, with statistical significance (t=5.755, －51.291; P＜0.05). Renal index, urinary glucose and UACR were significantly increased, while UCr was significantly decreased, with statistical significance (t=10.878, 137.273, 3.482, －6.110; P＜0.05). CREA decreased, TG, TC, HDL-C, LDL-C increased, and the differences were statistically significant (t=－28.012, 33.018, 118.018, 13.585, 16.480; P＜0.05). OCTA examination showed that there was no perfusion area of shallow retinal capillaries. The optical microscope showed that the inner boundary membrane of retina in model group was swollen and thickened, the surface was uneven, the inner and outer nuclear layer cells were disordered and the density decreased. Glomerular congestion was accompanied by cortical tubular epithelial swelling, widening of the mesangial area, and thickening of the basement membrane. The results of immunostaining showed that the inner and outer plexiform layers of the retina showed lamellar strong green fluorescence expression, and the inner and outer nuclear layers showed scattered dot green fluorescence expression. Transmission electron microscopy showed that the basal membrane of retinal microvessels in model group was slightly thickened, vascular endothelial cells edema, endothelial nucleus and perinucleus contraction, nuclear membrane contraction, mild mitochondrial swelling, vacuolation. ConclusionHigh-glucose and high-fat feeding plus a single intraperitoneal injection of STZ 35 mg/kg can successfully establish a microangiopathic model of type 2 diabetes.
【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.