Objective To investigate the effect of TIMP-2 gene that was transfected by adenovirus on extracellular matrix of abdominal aortic through assessing the changes of morphology and histopathology of the rat models with abdominal aortic aneurysm. Methods The rat models with abdominal aortic aneurysm were constructed by intraluminally perfusing porcine pancreatic elastase. Twenty-four SD rats with aneurysm were then randomly divided into 3 groups: AdTIMP-2 group (perfused locally with solution of TIMP-2 gene transfected by adenovirus vector to abdominal aorta), AdCMV group (transfected by non-viral vector), and PBS group. After 14 days, the concentrations of elastin and collagen that were collected from the samples of aortic wall were measured by image analysis system and the fixed aortic tissues were examined by light microscopy and some other specific staining methods. Results None of abdominal aortic aneurysm developed in TIMP-2 gene transfected group, with significantly higher rates of developed aneurysm in the other groups (P＜0.01). The diameters of arteries on day 14 in the AdTIMP-2 group were (2.33±0.06) mm, which were significantly smaller than those in the AdCMV group 〔（3.52±0.11） mm〕 and PBS group 〔（3.43±0.09） mm〕. The elastic fibers and collagenous fibers were preserved with more integrity in AdTIMP-2 group and inflammation cells that were observed in adventitia of artery were also less than those of the other groups. Conclusion TIMP-2 gene transfected by adenovirus vector could restore the degradation of extracellular matrix that was aroused by elastase and could block the formation of abdominal aortic aneurysm, which may provide a new strategy for the treatment of abdominal aortic aneurysm.
ObjectiveTo explore the effect of Aspergillus fumigatus on airway eosinophilia and hyperresponsiveness in rat model of chronic asthma. MethodsWistar rats were sensitized by intraperitoneal injections with ovalbumin (OVA) followed by chronic inhalation of nebulized OVA or physiologic saline. Rats were administered via the airways with placebo or aerosolized Aspergillus fumigatus spores suspension mimicking chronic Aspergillus fumigatus exposure. The Penh after acetylcholine provocation was detected using WBP system. The concentrations of IL-5 and eotaxin in BALF were measured by ELISA. The extents of eosinophil infiltration were evaluated on hematoxylin and eosin-stained(HE) and Wright-Giemsa stained BALF cells smear. ResultsAspergillus fumigatus worsened allergic airway inflammation in OVA-challenged rats,as evidenced by enhanced bronchial responsiveness to inhaled acetylcholine and increased bronchial eosinophilia. Elevated airway eosinophilia corresponded with higher levels of IL-5 and eotaxin in the Aspergillus Fumigatus exposure group. Aspergillus fumigatus,however,did not affect bronchial responses,numbers of eosinophils,IL-5 and eotaxin levels in saline challenged mice. ConclusionThe Results show that chronic Aspergillus fumigatus exposure aggravates eosinophilic airway inflammation in asthma rats by enhancing IL-5 and eotaxin production. Aspergillus fumigatus also increases bronchial hyperresponsiveness in asthma rats.
ObjectiveTo evaluate the influencing factors and explore a better method of making rat model of type 2 diabetes by high fat and sugar diet and streptozotocin(STZ) injection. MethodsSixty SPF grade of 6 weeks male SD rats were fed with high fat and glucose diet by 4 weeks and then randomly divided into 3 groups, the control group rats(n=20) were injected citric acid by 50 mg/kg and fed with normal diet, and the diabetes mellitus group rats were further divided into 2 subgroups by the different doses of STZ:the rats of diabetes mellitus model group 1(n=20) were injected by 50 mg/kg, while the rats of diabetes mellitus model group 2(n=20) were injected by 35 mg/kg. The diabetes mellitus model group rats were fed with high fat and glucose diet continually. The fasting blood glucose(FBG) were measured on day 3, 7, 10, and 14, respectively. The success model rate(blood glucose > 16.7 mmol/L after 14 days) and the mortality rate were calculated. Meanwhile fasting serum insulin level(FSI), total serum cholesterol(TC), and triglyceride(TG) were measured. ResultsCompared with the control group, the levels of FBG, FSI, TC, and TG were increased significantly in the diabetes mellitus model group 1 and 2(P < 0.05). And insulin sensitivity was worsen markedly(P < 0.05). But the diabetes mellitus model group 2 had higher success rate of making model(85% vs. 75%) and lower mortality(0 vs. 25%), P < 0.05. ConclusionRat model of type 2 diabetes induced by 4 weeks of high fat and sugar feeding and 35 mg/kg STZ injection has high morbidity, strongly security, and stable features.
ObjectiveTo provides an objective tool to evaluate rotator cuff function in rats. MethodsSixty adult male Sprague Dawley rats, weighing (281.21± 20.12) g, were involved in this experiment. Botulinum toxin A (6 U/kg) was injected into the infraspinatus of 12 rats in Botox group. Infraspinatus tendons of 12 rats in tear group were cut by microinvasive method. Infraspinatus tendons of 12 rats in sham-operation group were exposed but not cut. No any treatment was performed on the 12 rats in normal control group. One shoulder joint of each rat was selected randomly as treatment side. After 7 days, cadence, rate of stand phase, support pressure, swing speed, stand speed, and stride length of rats in those 4 groups were measured. Treatment side and contralateral side ratio of each gait parameter was caculated. If parameters of Botox group and tear group both showed significant differences compared with those of normal control group and sham-operation group, the gait parameter was brought into rating scale as an item. Each item was assigned from 1 point to 5 points according to gait parameter. The chronic rotator cuff injury model was established in 12 rats of verification group and rating scale was used to evaluate rotator cuff function each week for 8 weeks after surgery. ResultsAll gait parameters of tear group were significantly less than those of Botox group (P＜0.05), and Botox group was significantly less than sham-operation group and normal control group (P＜0.05), but no significant difference was found between sham-operation group and normal control group (P>0.05). All gait parameters were brought into rating scale as items. All items were rated from 1 point to 5 points, so the total score was 30 points and the lowest score was 6 points. Thirty points meant normal function of infraspinatus (rotator cuff function was normal), and 6 points meant complete loss of infraspinatus function (rotator cuff function was severely damaged). Rotator cuff functional scores of rats in verification group were 27.00±1.86, 23.75±2.83, 21.33±1.92, 18.17±2.37, 13.17±1.64, 11.67±2.50, 8.17±1.27, 6.50±0.67 from the 1st week to the 8th week respectively. ConclusionThe rating scale of rat rotator cuff function may reflect the severity of rotator cuff injury and the functional status of rotator cuff to some extent in rats.