Objective To investigate the effects of nitric oxide precursor L-arginine on traumatic pulmonary contusion. Methods Sixty Sprague-Dawley rats were randomly divided into three groups, ie. a normal group, a model group, and a L-arginine group. The model of traumatic pulmonary contusion was established with self-made chest-impacter. Then the rats in the L-arginine group was injected intravenously with L-arginine in a dose of 250 mg/kg. All rats were sacrificed at 24 hours after these models established.Levels of TNF-α and nitric oxide ( NO2 - /NO3- ) in serum were measured by ELISA and diazo-reaction method. Lung wet/dry weight ratio, NF-κB, endothelin-1, apoptotic cell, and ICAM-1 ( intercellular adhesion molecule-1) mRNA expressions in the lung tissue were measured. Results Compared with the model group,TNF-αand lung wet/dry weight ratio decreased significantly in the L-arginine group( P lt; 0. 05) . After the L-arginine treatment, the concentration of nitric oxide, apoptotic index were significantly higher than the model group ( P lt; 0. 05) . The expressions of NF-κB, endothelin-1, and ICAM-1 mRNA in the L-arginine group were lower than those in the model group ( P lt;0. 05) . Conclusion L-arginine treatment can downregulate the expressions of NF-κB, ET-1, ICAM-1 mRNA and apoptosis obviously, and ameliorate the microcirculation of rats lung with traumatic pulmonary contusion.
目的:研究呼吸操改善慢性阻塞性肺疾病(COPD)患者肺功能的机制。方法:对本院46例COPD 患者随机分成对照组和治疗组,按常规内科治疗并对其有计划地进行健康知识教育。治疗组在常规内科治疗加康复指导基础上,增加呼吸操训练。测定治疗前后6分钟步行距离、血清白三烯、呼出气中一氧化氮浓度(fractional exhaled nitric oxide, FENO)。结果:治疗组较对照组6分钟步行能力改善,血清白三烯水平下降(Plt;0.05)、呼气NO含量下降(Plt;0.05)。结论:加强COPD患者的健康指导及呼吸操训练可改善患者肺功能状况,明显提高生活质量
Objective To investigate the effect of inducible nitric oxide synth ase (iNOS) or cyclooxygenase－2 (COX－2) on retinal neovascularization and its possible mechanism in oxygen－induced retinopathy （OIR） mouse model. Methods Retinal neovascularization was induced by oxygen with different concentration. The expression of iNOS, COX－2, matrix metalloproteinases 2 (MMP－2) and vascular end othelial growth factor (VEGF) in the retinae of experimental animals were analyzed by immunohistochemistry, realtime polymerase chain reaction and western blotting technologies. Results The inhibition of COX－2 or iNOS obviously attenuated retinal neovascularization and decreased the expression of VEGF and MMP－2. The iNOS inhibition decreased COX－2 expression, and vice versa. Conclusions COX－2 and iNOS may play a role in retinal neovascularization in OIR mouse model, which may act by regulating the expression of VEGF and MMP－2.
Objective To observe the effects of culture medium of amniotic cells on NO and NOS in retinal tissues of rabbits in vitro in order to provide a protective method for antioxidation in retina transplantation. Methods Thirty adult healthy rabbits (30 right eyes) were divided into 3 groups. Group I: fresh retinal tissue; group II: routine culture medium; group III: culture medium of amniotic cells. The retinal tissues in group II and III were cultured in the corresponding culture medium for 1 week. The content of NO and NOS in retinal tissues in the 3 groups were determined. Results Compared with group I, the content of NO and NOS of group II increased obviously (t=3.821, 3.854; P＜0.001). There was no statistical difference of content of NO and NOS between group I and III (t=1.657, 1.745; P＞0.05). Conclusion Culture medium of amniotic cells may remove free radicals and enhance the ability of antioxidation. (Chin J Ocul Fundus Dis，2004，20：366-368)
Objective To explore the correlation between the levels of nitrite / nitrate( NO2 /NO3) in exhaled breath condensate ( EBC) and pulmonary infection in mechanically ventilated patients. Methods The clinical data from ventilated patients in critical care units of Peking University People’s Hospital from November 2006 to August 2007 were collected and analyzed. The patients’clinical pulmonary index score ( CPIS) were calculated. EBC of those patients were collected via endotracheal tube or tracheostomy cannula,and the concentrations of NO2 /NO3 were assayed. The level of NO2 /NO3 in different CPIS patients in 24 hours’ventilation, weaning proportion in 3 days and mortality in different NO2 /NO3 level patients were compared. The correlation of the CPIS and level of NO2 /NO3 were explored between survival and non-survival patients. Results A total of 76 patients were enroled. The NO2 /NO3 levels in patients of CPIS≤3, CPIS 3-6 and CPIS gt;6 in 24 hours of ventilation were ( 23. 31 ±5. 79) , ( 28. 72 ±9. 10) and ( 35. 42 ±12. 10) μmol / L respectively, with significantly differences between each other ( P lt; 0. 01) . The lower the patients’concentration of NO2 /NO3 was, the earlier the weaning and the lower the mortality were. The NO2 /NO3 levels on 4th and 7th day were detected in 24 survival patients and 23 non-survival patients. The difference of NO2 /NO3 levels between the survival patients and non-survival patients became significant on 7th day [ ( 29. 32 ±9. 52) μmol / L vs. ( 37. 22 ±12. 03) μmol / L, P lt; 0. 01] . Linear correlation analysis showed that the NO2 /NO3 level was positively correlated with CPIS ( r = 0. 76, P lt; 0. 01) . Conclusions The NO2 /NO3 level of EBC in ventilated patients is positively correlated to the severity of pulmonary infection, thus may be used as a new predictor for weaning and prognosis.
OBJECTIVE To study the protective effects of Schwann cell derived neurotrophic factor (SDNF) on motoneurons of spinal anterior horn from spinal root avulsion induced cell death. METHODS Twenty SD rats were made the animal model of C6.7 spinal root avulsion induced motoneuron degeneration, and SDNF was applied at the lesion site of spinal cord once a week. After three weeks, the C6.7 spinal region was dissected out for motoneuron count, morphological analysis and nitric oxide synthase (NOS) enzyme histochemistry. RESULTS 68.6% motoneurons of spinal anterior horn death were occurred after 3 weeks following surgery, the size of survivors was significantly atrophy and NOS positive neurons increased. However, in animals which received SDNF treatment, the death of motoneurons was significantly decreased, the atrophy of surviving motoneurons was prevented, and expression of NOS was inhibited. CONCLUSION SDNF can prevent the death of motoneurons following spinal root avulsion. Nitric oxide may play a role in these injury induced motoneuron death.