Objective To investigate the relationship between surgical operation and hypophosphatemia, to observe the possible damage of hypophosphatemia and to assess the value of postoperative phosphate supplementation. Methods Sixty four male SD rats were randomly divided into 2 groups, Group Ⅰ, drinking a specially prepared solution to reduce their phosphate storage, Group Ⅱ, drinking water as a control. All received common bile duct ligation 3 weeks later. The serum biochemical data including phosphate level were obtained before and after operation. Then half of rats in each group were supplied with NaH2PO4 5-day survival rates were analyzed with statistic methods and their vital organs were observed under electron microscope. Results The phosphate level of each group was descended after operation. The group with phosphate shortage before operation (group Ⅰ) had a greatest fall of phosphate and average arterial pressure. The phosphate-supplied rats had a minor change of vital organs under electron microscope scan and higher 5-day survival rate compared to others in this group.Conclusion Abdominal surgery may induce postoperative hypophosphatemia, especially when the phosphate has been lacking before operation. Severe hypophosphatemia, superimposed on surgical trauma, enhances the damage to the body. Prompt supplement of phosphate will improve the prognosis of surgical operation.
Objective To provide a reliable experimental model for gastroesophageal reflux (GER) study. Methods Twenty Japan 5-month-old male rabbits wererandomly divided into two groups: group cardiomyotomy(n=10), group partial cardiomyectomy(n=10). The operations of cardiomyotomy and parital cardiomyectomy were performed in 2 groups respectively. All the animals underwent intraesophagealpH detection 1 week before operation and 4 weeks after operation. The mean changes of reflux ratios were compared between before operation and after operation.Results In gastroesophageal reflux ratio between before operation and after operation, there was no significant difference in group cardiomyotomy (1.98%±1.52% and 4.32%±2.39%, Pgt;0.05) and there was significant difference in group partialcardiomyectomy（1.56%±1.57% and 13.56%±3.27%, Plt;0.05）. Conclusion The reliable experimental model of GER can be made with procedure of partial cardiomyectomy. It can be used in estimating the operative procedure of antireflux and is conducive to dynamic observation and study of esophagitis.
Objective To explore the feasibility and operation points of establishing duodenal-jejunal bypass （DJB）surgery animal model in Goto-Kakizaki （GK） rats. Methods Sixteen GK rats were randomly divided into experimental group （n=8） and control group （n=8）. In a standardized preoperative， intraoperative， and postoperative operation， the rats of experimental group and control group received DJB and sham surgery respectively. The fasting plasma glucose and body mass were observed before operation， and 1， 2， 3， and 4 weeks after operation in order to evaluate whether the models were established successfully. Survival situation of rats were observed too. Results All experimental rats survived at 4 weeks after the operation. Compared with the levels before operation， the fasting plasma glucose levels of experimental group decreased significantly （P＜0.05） at 1 week after operation， and remained stable at 2， 3， and 4 weeks after operation.The fasting plasma glucose levels of control group did not change statistically at all time points after operation （P＞0.05）. Compared with control group at the same time point， the fasting plasma glucose level of experimental group was lower （P＜0.05）， indicating that DJB models were established successfully. After 4 weeks， the value of body mass added in experimental group was significantly lower than those of control group （P＜0.05）. Conclusions DJB is a feasible， safe， and effective hypoglycemic surgery. The application of this set of experimental operating procedures can reduce the risk of intraoperative and postoperative mortality， and can develop a stable DJB model in Goto-Kakizaki rats.
To make a rabbit model of Perthes disease and to explore the change and its significance of VEGF expression in the femoral head. Methods Twenty-four 3-month-old New Zealand rabbits (weighing 1.6-1.8 kg) were randomly divided into experimental group (n=16) and control group (n=8). A rabbit model of Perthes disease was made by excision of left l igamentum teres and retinacular blood suppl ies of femoral head. The gross appearance, X-ray film and histological observations were made and the immunohistochemistry and VEGF mRNA in situ hybridization were carried out1, 2, 4, 8 weeks after operation. Results The rabbit model of Perthes disease was made successfully; only 1 was infected5 days after operation and was made quit. The gross appearance: The femoral heads had no necrosis changes in control group at every time. The femoral heads became coarse, tarnish and smaller, and even collapsed in experimental group. The HE staining observation: The femoral heads had no necrosis changes in control group at every time after operations. New vessels and granulation tissues grew into the necrosis part in the experimental group 4 weeks and 8 weeks after operations. New bone could be seen in repaired bone. Immunohistochemistry staining: In the epiphyseal cartilage of the femoral heads in control group, an intensive VEGF immunoreactivity (VEGF-IR) was found in the hypertrophic zone with a low level of VEGF-IR in the prol iferative zone. At 1 week after operation, the percentage of VEGF+ cells in the prol iferative zone of the femoral heads in experimental group was increased compared with that of the femoral heads in control group. The percentage of VEGF+ cells in the hypertrophic zone of the femoral heads in experimental group was significantly decreased compared with that of the femoral heads in control group. At 8 weeks after operation, VEGF-IR was observed throughout the epiphyseal cartilage surrounding the bony epiphysis in the femoral heads in experimental group. The percentage of VEGF-positive cells in the prol iferative zone of the femoral heads in experimental group was significantly increased compared with that of the normal heads. The hypertrophiczone of the femoral heads in experimental group had a similar percentage of the VEGF+ cells to the femoral heads in control group when endochondral ossification was restored at 8 weeks. There were statistically significant differences in the ratios of VEGF+ cells in the prol iferative zone of femoral head 1, 2, 4, 8 weeks after operations (P lt; 0.01); in the ratios of VEGF+ cells in the hypotrophic zone of femoral head 1, 2, 4 weeks after operations (P lt; 0.01) between experimental group and control group. In situ hybridization results: The results were similar to that of histology. VEGF mRNA expression in the hypertrophic zone of epiphyseal catilage after necrosis were lower. VEGF mRNA expression in the prol iferative zone of epiphyseal catilage after necrosis increased. VEGF mRNA expression in the hypertrophic zone of epiphyseal cartilage in experimental group could be seen again after endochondral ossification was repaired. Conclusion It is possible that VEGF may act as a key regulator that couples angiogenesis, cartilage remodel ing, and ossification after ischemic damage to restore endochondral ossification in the epiphyseal cartilage.
ObjectiveTo explore the feasibility of goat tricuspid regurgitation (TR) model by one chordae tendineae cutter via right anterior-lateral minimal incision.MethodsTR model was established in 6 goats with a self-made tricuspid valve chordae tendineae cutter. The goats were placed in a left lateral position and procedure was performed via a right anterior-lateral minimal thoracotomy in the fourth intercostal. Under the guidance of transesophageal ultrasound and digital subtraction angiography, the chordae tendineae of anterior leaflet was cut until moderate to severe regurgitation was confirmed. Echocardiography and laboratory examinations were performed preoperatively, immediately and 3 months after surgery. Additionally, all goats were sacrificed to clarify pathological evaluation.ResultsTR was successfully established in 6 goats. The right atrium pressure increased significantly immediately after surgery (P<0.05). During a follow-up of 3 months, the progression of TR was aggravated (P<0.05), and the annular diameter increased from 2.15±0.23 cm to 2.65±0.20 cm. Overall, there was no statistically significant change in transvalvular gradient and velocity between preoperation and postoperation. Laboratory test results showed no abnormalities between preoperation and postoperation. Autopsy evaluation demonstrated obvioue chordae tendineae transection of the anterior leaflet.ConclusionIt is feasible to establish TR model via a right minimal anterior lateral thoracotomy in the fourth intercostal space. This novel TR goats model will allow investigation of transcatheter interventional device and serve as a chronic model in the future.
Objective To summarize the research progress on rodent models of cervical spinal cord injury (SCI). Methods The relevant domestic and foreign literature in recent years was reviewed, the methods of establishing the rodent models of cervical SCI and the evaluation methods of behavior, imaging, neuroelectrophysiology, and histology were summarized. Results Cervical SCI involves primary and secondary injuries. Primary cervical SCI can be simulated with contusion, contusion compression, fracture dislocation, spinal cord traction, and spinal cord transection; scondary cervical SCI can be simulated with photochemical model and excitotoxicity model. Certain evaluation methods such as behavior, imaging, neuroelectrophysiology, and histology are used to evaluation during model building and research. Conclusion Different rodent models of cervical SCI have different advantages and application directions, and it is critical importance for the study of cervical SCI to establish effective animal models.
A acute partial obstructive hepatocholangitis model by selective ligation and injection of E coli into left hepatic bile duct was successfully founded in rat. Using parameters including mortality, mitochondrial glutamic oxalacetic transaminase and ornithine carbamoytransferase activity, pathological observation and blood culture of bacteria, we evaluated the model. The authors emphasize that this models is superior to the wole-bile-duct-challenged cholangitis model, which is characterized by liver injury.
Objective To establ ish the experimental animal model of perforator sural neurocutaneous flap for laying a foundation of further study on its physiology and haemodynamics. Methods Thirty-five New Zealand rabbits were divided into four groups, weighing 2.5-3.0 kg and being male or female. In group A (n=5), vivisection was performed to observe thestarting point and arrangement of sural nerve, its concomitant vessels, posterior tibial artery and perforating vessel. In groups B and C (n=5), red latex and gelatin-lead oxide were injected into the concomitant arteries of sural nerve and the posterior tibial arteries respectively to observe their arrangement, the diameter and anatomasis. In group D, forty neurocutaneous flaps based on single perforator were elevated in the twenty rabbits with a size of 7 cm × 1 cm and a pedicle of 0.5 cm. The colour and condition of flaps were observed. Results The sural nerve originated from posterior tibial nerve, passed through the lateral head of the gastrocnemius at site of the popl iteal fossa, descended obl iquely to exterior, entered in the deep fascia at about (5.42 ± 0.15) cm above lateral malleolus, and descended vertically to lateral malleolus. Its concomitant artery originated from deep femoral artery with an initial diameter of (0.73 ± 0.11) mm and extended to the lateral malleolus along the sural nerve. A perforating branch of posterior tibial artery at the position of the calcaneus originated from the midpoint of the l ine connecting between the medial malleolus and the calcaneus with an initial diameter of (0.45 ± 0.01) mm. The perforating branch traversed the calcaneus to the region of the lateral malleolus, and anastomosed to the concomitant artery of the sural nerve, forming a vascular plexus around the sural nerve. In group D, two cases were excluded due to infection. The survival rate was 78.0% ± 1.5% in other 38 flaps 10days after operation. Conclusion The perforator based sural neurocutaneous flap in rabbit is a good experimental model,which has stable anamatic features and rel iable blood distribution.
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.