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.
ObjectiveTo explore the predictive value of fractional exhaled nitric oxide (FeNO) in the treatment response of adult asthmatic patients. Methods64 adult outpatients with asthma from Peking Union Hospital between March and September 2013 were recruited in the study. All patients completed asthma control test (ACT) together with exhaled nitric oxide (FeNO) and pulmonary function test. Then the patients were classified into a higher FeNO group (n=33) and a normal FeNO group (n=31) according to FeNO level. All patients accepted regular inhaled ICS/LABA treatment (salmeterol and fluticasone 50/250). Three months later all patients reaccepted ACT,FeNO and pulmonary function test. ResultsThe ACT score increased in all patients,and was significantly higher in the higher FeNO group than that in the normal FeNO group[22.07±5.49 vs. 19.23±5.48,t=2.893,P<0.05]. The complete control rate of the higher FeNO group was higher than that in the normal FeNO group (42.42% vs. 19.35%,χ2=3.960,P<0.05). The FEV1 and FEV1%pred of two groups both increased significantly (P<0.05),but there was no significant difference between two groups (P>0.05). Correlation analysis showed that FeNO and the declined rate of FeNO was negatively correlated with the ACT score(r=-0.302,P<0.05;r=0.674,P<0.01) and positively correlated with the improvement of ACT score (r=0.514,P<0.01;r=0.674,P<0.01). No significant correlation was found between FeNO and FEV1 or FEV1%pred. ConclusionThe effect of ICS/LABA therapy is better for asthma patients with higher FeNO. FeNO can be used for predicting the response to ICS/LABA therapy in patients with asthma and guiding the treatment.
ObjectiveTo understand the effect of nitric oxide (NO) on the formation of hyperdynamic circulatory syndrome (HCS) and the influence of level of NO on HCS. MethodsAfter establishment of stable HCS in partial portal vein ligated rats,the quantity of NO in blood of portal vein and the activity of nitric oxide synthase (NOS) in liver were determined by pre and post injection of inhabitor of NOS (NGmethylLarginine) and hemodynamics was supervised simultaneously.ResultsThe quantity of NO was paralleled with the activity of NOS and was elevated markedly by 24 hours after operation and reached the top by 48 hours after surgery. These sequential changes were coincided with the dilation of general vascularture. There was a close relation between this changes and the formation of HCS.The quantity of NO and the activity of NOS were decreased significantly to the level of the control group after injection of NGmethylLarginine (LNMMA). LNMMA inhabited the activity of NOS and blocked the production of NO. HCS ameliorated obviously. ConclusionNO plays an important role in initiating the dilation of general vascularture and plays a critical role in the formation of HCS. HCS will be ameliorated obviously or be blocked completely by eliminating the effect of NO and the portal pressure will decreased significantly or recover to normal range.
Objective To investigate the pathogenesis of acute lung injury in rats induced by intra-peritoneally injection of perforative peritonitis ascitic fluids(PPAF) and the role of L-arginine (L-Arg) in acute lung injury in this model. Methods Perforative peritonitis (PP) models were established in 60 rats and PPAF were collected. Forty-eight rats were randomly divided equally into NS group,PPAF group, and L-Arg group. Rats were randomly subjected to death at 7 h and 12 h. Peripheral blood WBC were counted,levels of NO and malondialdehyde (MDA) in serum were examined. Lung injury score and wet/dry ratio were evaluated, and level of myeloperoxidase (MPO) in lung tissues and lung cell apoptosis were tested. Results WBC count of peripheral blood, levels of NO and MDA in serum, level of MPO in lung tissue, lung injury score, wet/dry ratio, and lung cell apoptosis rate in PPAF group were significantly higher than that in NS group at each time point(P<0.01). Level of NO in serum in L-Arg group was higher than that in PPAF group (P<0.01), but lower level of MDA in serum, lower level of MPO in lung tissue and lung injury score,lower wet/dry ratio, and lung cell apoptosis rate were observed in L-Arg group(P<0.05). In PPAF group and L-Arg group, level of NO in serum, wet/dry ratio, and lung cell apoptosis rate were higher at 12 h than that at 7 h(P=0.000). Serum NO level was in negative correlation with serum MDA level (r=-0.257,P=0.021), MPO level in lung tissue(r=-0.444, P=0.011),and lung cell apoptosis(r=-0.351, P =0.010) in PPAF group and L-Arg group, but serum MDA level was in positive correlation with cell apoptosis(r=0.969, P<0.001) in each group. Conclusions Acute lung injury rats model can be established by intra-peritoneally injection of PPAF. Enhanced oxidizing reaction and cell apoptosis take part in the occurrence of acute lung injury. L-Arg plays a protective role in acute lung injury.
Objective To study the changes of endothelin (ET) and nitric oxide (NO) in the local site of vein transfer with delayed breaking pedicle and the relation with vasospasm and vein transfer in rabbits. MethodsThe ET concentration of blood was determined with the radioimmunoassay method. The plasma NO-2,NO-3 levels in the local site of vein transfer with delayed breaking pedicle, which reflected NO levels indirectly, were detected with Ultravioletvisible (UvVIS ) spectrophotometer. ResultsThe endothelin concentration of blood was increased significantly at 2, 4 hour after the operation (P<0.01), and at 8 hour after the operation (P<0.05). The plasma NO level was significantly decreased at 2, 4 hour after the operation (P<0.01). But at 24 hour after the operation, the plasma NO level was increased significantly (P<0.05). Conclusion The recovery of ET concentration of blood and the increase of plasma NO at 24 hour after the operation are the cause of the reduced incidence of vascular crisis of vein transfer with delayed breaking pedicle, and the very time point is the optimum moment for pedicle breaking.
Objective To study the effect of the competitive inhibitor of nitric oxide synthase NG-nitro-L-arginine methyl ester (LNAME) on thedenervated muscle atrophy. Methods A model of the denervated gastrocnemius atthe right lower limb was established in 36 SD adult rats. The rats were randomly divided into two groups: the L-NAMEgroup (Group A) and the control group(Group B). L-NAME 10 mg/ kg daily was injected into the denervated gastrocnemius inGroup A, and normal saline was injected into the denervated gastrocnemius in Group B. At 2, 4 and 8 weeks after operation, the rate of the muscle wet weight preservation, the cross section area of the myocyte, the protein amount, and the percentage of the apoptotic muscle cells were measured respectively and the ultramicrostructure of the myocyte was observed. Results At 2 and 4 weeks after operation, the rate of the muscle wet weight preservation, the cross section area of themyocyte, and the protein amount were significantly greater in Group A than in Group B; however, the percentage of the apoptotic muscle cells was significantly smaller in Group A than in Group B. The observation of the ultramicrostructure of themyocyte showed that an injection of L-NAME could protect the ultramicrostructure of themyocyte. At 8 weeks after operation, there was no significant difference between the two groups in the abovementioned parameters. Conclusion The nitric oxide synthase inhibition can delay the denervated muscle atrophy.