首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
AIM: To investigate the effect of nitric oxide (NO) in ocular inflammation after intraocular lens implantation. METHODS: All New Zealand rabbits were divided randomly into three groups: 1. control group, 2. L-arginine (L-Arg) group, 3. N-nitro-L-arginine (L-NNA) group. Extracapsular cataract extraction (ECCE) and posterior chamber intraocular lens implantation (IOL) were operated in all animals of each groups. The inflammatory response of all rabbit eyes, including cornea edema and anterior chamber exudation were investigated 1, 3, 7, 14, 30 days afteroperation. Meanwhile, aqueous humor was drawn for white blood cell (WBC) counting and classifying, as well as for NO2-/NO3- measurement. RESULTS:NO2-/NO3- contents, total WBC and anterior chamber exudation in aqueous humor of L-Arg group were higher than that in control group. While that of L-NNA group were lower than that in control group.CONCLUSION:NO plays a role in intraocular inflammatory response after intraocular lens implantation. L-NNA, a nitric oxide synthase exhibitor, decreased NO contents, therefore it may reduce intraocular inflammatory response after intraocular lens implantation.  相似文献   

2.
AIM:To observe the changes of iNOS and eNOS in lung tissue and NO in bronchoalveolar lavage fluid (BALF) in smoking rats.METHODS:80 Wistar rats were divided into control, smoking group, L-NIL group and L-NAME group (rats were exposed to smoke and injected (i.p.) with selective iNOS inhibitor L-NIL or NOS inhibitor L-NAME). iNOS and eNOS protein levels in whole lung were detected by immunohistochemical staining, and NOS mRNA was quantified using RT-PCR. In addition, NO2-/NO3- was determined using Griess assay.RESULTS:The expression of iNOS mRNA and protein in smoking rats increased, the expression of eNOS mRNA and eNOS protein decreased, and the total cell count and the level of NO2-/NO3-in BALF increased(P＜0.05). In vivo, L-NIL reduced the total cell count and NO2-/NO3- in BALF (P＜0.05), while L-NAME had no effect on them.CONCLUSION:Cigarette smoke increased expression of iNOS mRNA and protein and decreased expression of eNOS mRNA and protein. The large amount of NO generated by iNOS may amplify inflammation in lung tissue.  相似文献   

3.
AIM: To approach the changes of ET and NO levels of mice bearing sarcoma 180 (S180 ) during different period(5、10 and 15 days) and the relationship between ET、NO and tumor’s development METHODS: Adopting mice bearing S180 as the models, the levels of ET and NO2-/NO3- in serum were detected, and the weight of isolated tumors was measured On the basis of the regulation of these changes, their relationships were explored RESULTS: The levels of ET and NO2-/NO3- of mice bearing S180 were higher than that of the control group (not bearing tumor) ( P< 0.05) Along with the development of the tumors, the levels of NO2-/NO3-and tumors weight both increased ( P< 0 05) ET also had an increasing tendency There was a positive correlation between the level of NO2-/NO3- and tumor weight ( r =0.995, P< 0.05) Ratio value of (NO2-/NO3-)/ET decreased at first and then increased CONCLUSION: ET and NO have links with the development of S180 There may be cooperation between ET and NO during the development of tumor.  相似文献   

4.
AIM: To study the relationship between the disturbance of nitric oxide/endothelin-1(NO/ET-1) and hepatic ischemia/reperfusion(I/R) injury as well as the regulation of NO/ET-1 system by hepatic ischemic preconditioning(IPC). METHODS: The changes of NO/ET-1 system and their relationship with hepatic I/R injury were compared between I/R group and IPC+I/R group in a rat hepatic I/R model. Two hours after reperfusion, the liver tissues were detected by RT-PCR to see whether there was inducible nitric oxide synthase (iNOS) mRNA expression. RESULTS:In the acute phase of hepatic reperfusion, the ratio of NO/ET-1 was reduced, which was due to a significant reduction of NO2-/NO3- (the metabolic product of NO) and significant elevation of ET-1 in the blood plasma. The content of ALT, AST, LDH and TNF-α in blood plasma, and of MDA in liver tissue were increased but ATP in liver tissue was reduced, the hepatic damage was deteriorated. The protection of the hepatic IPC was concerned with the elevation of the ratio of NO/ET-1 caused by the elevation of NO2-/NO3-, and reduction of ET-1 as well. There was no iNOS mRNA detected in the liver tissues.CONCLUSION: Hepatic I/R injury is related to the disturbance of NO/ET-1. The protection of the hepatic IPC in the acute phase might be conducted by its regulation of NO/ET-1 system. The cNOS rather than the iNOS generated the NO in this situation.  相似文献   

5.
AIM: To investigate the effects of nitric oxide (NO) on hepatic encephalopathy in cirrhotic rats induced by LPS. METHODS: The cirrhotic model of rats was established by complex pathogeny. Since the end of the 8 th week, the rats were intragastrically-infused with 0.9% salt, L-arginine(L-arg) and LNNA respectively for 2 weeks.The hepatic encephalopathy in cirrhotic rats were induced by 3 mg/kg LPS (ip) 4 hours before the rats were sacrificed. RESULTS: The normal behaviors and electroencephalograph were appeared in L-arg group. LNNA group showed hepatic encephalopathy. The content of NO2-/NO3- of brain tissue was markedly higher in L-arg group than LNNA group(P<0.05), but the content of histamine in brain tissue was lower in L-arg group than LNNA group(P<0.05). There was a negative correlation between the content of histamine in brain tissue and the content of NO2-/NO3- of brain tissue. CONCLUSION: NO can prevent hepatic encephalopathy in cirrhotic rats induced by LPS.  相似文献   

6.
AIM: To observe the kinetic alteration of nitric oxide formation in the lungs in the development of pulmonary fibrosis in the rat. METHODS: The contents of hydroxyproline in the lungs, NO2-/NO3- (nitrite/nitrate) in out-flowing and in-flowing pulmonary blood (OPB, IPB) were assayed on the day 7, 14, 21, 30 and 70 after intratracheal administration of bleomycin A5 . The content of NO2-/NO3- in supernatants of culture of the alveolar macrophages (AMs) and the amount of iNOS positive stain cells in lung tissue section were also observed in the rat on 14th day after-bleomycin A5 administration. RESULTS: The content of lung hydroxyproline had no change on the 7th day, increased on the 14th day (P＜0.05), increased significantly on the 21th day, 30th day and 70th day post-bleomycin A5 compared with control rats. On the 7th day and 14th day, the content of NO- 2 /NO3- increased in OPB and decreased in IPB (P＜0.01). On the 21th day, the content of NO2-/NO3- abated in OPB (P＞0.05) but still decreased in IPB (P＜0.01). On the 30th day and the 70th day, the NO2-/NO3- level recovered both in OPB and IPB. AMs from rats on the 14th day post-bleomycin A5 showed significant elevation (P＜0.01) in NO2-/NO3- level. The amount of iNOS positive stain cells increased in rats on the 14th day post-bleomycin A5. CONCLUSION: The amount of NO in the lungs was high in the initial phase of fibroproliferative reaction induced by bleomycin A5 ,and these might be associated with the enhanced ability of AMs to release NO and the increased amount of iNOS.  相似文献   

7.
AIM: To investigate the changes in nNOS and iNOS expression of hippocampal CA3 pyramidal neurons and NO2-/NO3- level of hippocampal homogenate of rats induced by stress, and to explore the effect of phenytoin on them. METHODS: Rats were subjected to forced-swimming stress, phenytoin was administered(ip) at 30 min before stress. Using the immunohistochemistry and the computerized image technique, the expression levels of nNOS and iNOS of rat hippocampal CA3 pyramidal neurons were assayed quantitatively, and the NO2-/NO3- level of hippocampal homogenate was also measured using nitric acid deoxidize enzyme method. RESULTS: The nNOS average grey degree of hippocampal CA3 pyramidal neurons was significantly lower in stress group (155.42±3.77)than that in control group(164.54±4.62)and in stress plus phenytoin group(164.27±2.55)(P<0.01); The iNOS relative sectional area proportion of hippocampal CA3 pyramidal neuron was significantly larger in stress group(5.87%±2.90%) than that in control group (0.90％±0.89%) and in strers plus phenytoin groups (0.90%±0.88%)(P<0.01); The NO2-/NO3- level of hippocampal homogenate was significantly higher in stress group(42.75 umol/L±14.49 umol/L)than that in control group(21.23 umol/L±6.99 umol/L)and in stress plus phenytoin group(18.40 umol/L±8.11 umol/L)(P<0.01). CONCLUSION: It is suggested that the stress could induce nNOS and iNOS expression in CA3 pyramidal neurons and excessive production of NO in hippocampus of rats, which could be inhibited by phenytoin.  相似文献   

8.
AIM: To study the effects of nitric oxide (NO) on mitochondrial damage caused by exogenous calcium. METHODS: Normal myocardial mitochondria were divided into three groups; L-arginine control group (CG), Ca2＋-damaged group (DG) and L-NAME-preserved group (PG). Mitochondria of all groups were incubated at 30 ℃ with reaction medium containing 20 μmol/L EDTA, 100 μmol/L CaCl2 and 1 μmol/L L-NAME with 100 μmol/L CaCl2 respectively. Then the NO2-/NO3- contents, mitochondrial viability and membrane potential were investigated. RESULTS: The NO2-/NO3- contents of DG was obviously higher than that of CG and PG, meanwhile, there was no obvious difference between CG and PG. Mitochondrial viability and membrane potential of DG were significantly lower than that of CG and PG, and negatively related to NO-2/NO-3 contents (r=-0.5297, P＜0.01; r=-0.6041, P＜0.01). But, the mitochondrial viability and membrane potential of PG were still lower than that of CG. CONCLUSION: Exogenous calcium could activate mitochondrial nitric oxide synthase resulting in NO production and the latter play an important role in decreasing mitochondrial viability and membrane potential.  相似文献   

9.
AIM:To investigate the effect of Se-containing spirulina phycocyanin (Se-SPC) on liver injury of mice induced by carbon tetrachloride (CCl4). METHODS:The mouse model was conducted by intragastric feeding with 2% CCl4 oil for three times, meanwhile Se-SPC, spirulina phycocyanin (SPC) and Na2SeO3 were injected (ip) to various groups for 7 days. Then selenium (Se), glutathione peroxidase (GPx), superoxide dismutase (SOD), alanine aminotransferase (ALT), malondiaoldehyde (MDA) and nitric oxide (NO) levels in blood and liver were measured. RESULTS:The level of Se,GPx and SOD activities were obviously higher(P<0.05)but ALT activity,MDA and NO2-/NO3- levels were remarkably lower(P<0.05)in Se-SPC treated groups than those in CCl4 groups,and effects of high dose Se-SPC on Se,GPx,MDA and NO2-/NO3- were even more significant(P<0.01).Under the same dose of Se or protein,effects of all selected targets in Se-SPC groups were more efficient than those in SPC groups and inorganic-Se groups.Furthermore,Se levels had a positive correlation with GPx activity(r=01705),which had negative correlation with levels of MDA,NO2-/NO3- and ALT(r=-0.629,r=-0.336,r=-0.457,respectively), and positive correlations between ALT activity and MDA or NO2-/NO3- level were found (r=0.519,r=0.641). CONCLUSION:These results indicated that Se-SPC may attenuate liver injury of mice induced by CCl4 through its anti-inflammatory action and enhancing selenoenzyme expression.  相似文献   

10.
采用水培方法,以常规营养液（7.5 mmol·L-1 NO3-）、叶面喷施清水作为对照, 在75 mmol·L-1 NO3-胁迫下,通过叶面喷施0 mmol·L-1（T1）、1 mmol·L-1（T2）、5 mmol·L-1（T3）的蔗糖,研究外源蔗糖对NO3-胁迫下叶用莴苣生长及品质的影响。结果表明：T1 处理叶用莴苣的生长受到显著抑制,同时显著降低了VC 含量。外源蔗糖处理可以缓解NO3- 胁迫对叶用莴苣生长的抑制作用,提高VC 含量,同时可略降低硝酸盐含量,其中T2 处理效果较好。与对照相比,T2 处理和T3 处理均可降低叶用莴苣可溶性蛋白含量,T3 处理可提高可溶性糖含量,但差异均不显著。  相似文献   

11.
AIM: To explore the effect of antiserum against rat complement C5b-9 complexes on nitric oxide synthesis and pathologic changes in renal tissue of rats with mesangioproliferative glomerulonephritis. METHEDS: The rat model of mesangioproliferative glomerulonephritis,namely,anti-thymocyte serum nephritis(ATSN) was established and the rats with ATSN were treated with antiserum against complement C5b-9 complexes. Some parameters related to NO and pathologic changes of the rats were observed.RESULTS: Anti-C5b-9 serum not only reduced the expression of inducible NO synthase(iNOS) mRNA in renal tissue and urinary content of nitrate/nitrite(NO3-/ NO2-) of rats with ATSN, but also reduced renal pathologic changes. L-N G-nitro arginine methylester (L-NAME) also reduced the contents of urinary NO3-/NO2- and the renal pathologic changes of rats with ATSN. CONCLUSION: The antiserum against rat complement C5b-9 complexes inhibited glomerular NO synthesis and glomerular mesangial cell proliferation of rats with ATSN.  相似文献   

12.
AIM:To observe the dynamic changes of plasma levels of nitric oxide(NO) and endothelin (ET-1) in portal veins of the rats during prehepatic portal hypertension, and investigate the role of them in hyperdynamic circulation.METHODS:The models of prehepatic portal hypertension were established in Sprague-Dawley rats by means of partial portal vein ligation (PVL). The plasma levels of nitrite/nitrate (NO2-/NO3-) and ET-1 in the portal veins were detected by the method of nitric reductase and radioimmunoassay, respectively. In this study, rats were divided into normal, sham operation (SO) and PVL group. SO and PVL rats were divided into several subgroups according to different time after operations. Meanwhile, the changes of several hemodynamic indexes in these rats were also measured.RESULTS:The levels of NO2-/NO3- were significantly increased and ET-1 were significantly decreased in rats at different time after PVL compared with normal control, whereas the hemodynamic indexes changed accordingly.CONCLUSION:The portal hypertensive rats are in hyperdynamic circulatory state (HCS). NO and ET-1 may play an important role in the induction and maintenance of HCS.  相似文献   

13.
AIM: To study the role of high level of endogenous nitric oxide (NO) in apoptosis of alveolar epithelial cells in the development of pulmonary fibrosis in rats. METHODS: The content of nitrite/nitrate (NO2-/NO3-) in out-flowing pulmonary blood (OPB) was assayed by nitric acid reduction method. The apoptosis of alveolar epithelial cells was observed by TdT-mediated dUTP nick-end labeling (TUNEL) and electron microscopy, respectively. The above indices were observed on the day 14 and the day 30 after intratracheal administration of BLMA5 alone or along with blockade of iNOS by aminoguanidine (AG) in rats. RESULTS: (1) Both the content of NO2-/NO3- in OPB and the number of apoptotic alveolar epithelial cells in lung were increased in BLMA5 14 d group, compared with normal control group and BLMA5 30 d group, respectively (P<0.05). The high level of NO2-/NO3- in OPB and the apoptosis of alveolar epithelial cells were ameliorated by AG. CONCLUSION: The apoptosis of alveolar epithelial cell is induced by high level of endogenous NO in the development of pulmonary fibrosis.  相似文献   

14.
AIM:To investigate the effect of glycine on endotoxin and hypoxia-induced necrotizing exterocolitos (NEC) in rats. METHODS:In glycine+NEC group, twenty anesthetized and artificially ventilated rats received 1g/kg glycine (20%, iv). Five minutes later, the rats were treated with 2 mg/kg lipopolysaccharide (LPS). In control group (NS+NEC), twenty rats were treated with normal saline as a substitute for glycine. In all animals, FiO2 was reduced after 90 min from 21% to 5% and ventilation continued until 180 min or death. At the end of the experiment, the samples of blood and intestine were obtained immediately. Serum TNFα was measured with ELISA, serum NO was determined by nitrate reductase. The histopathology of the necrotic lesions were categoried: grade Ⅰ, focal mild injury confined to villous tips; grade Ⅱ, partial loss of villi; grade Ⅲ, necrosis extending to submucosa; grade Ⅳ, transmural necrosis. RESULTS:The survival time was shorter in the NS+NEC group (P＜0.01). The intestinal injury of the rats in glycine+NEC group was markedly alleviated (P＜0.01). The levels of TNF-α and NO2-/NO3- in serum decreased significantly in animals treated with glycine (P＜0.01, P＜0.05). CONCLUSION:Glycine alleviated LPS-induced NEC by inhibiting excessive production of TNFα and nitric oxide.  相似文献   

15.
AIM: To explore the mechanism of the nitric oxide (NO) synthesis induced by human C5b-9 complex in glomerular mesangial cells(MC) of rats. METHODS: The MC of rats were cultured and stimulated with human complement C5b-9 complex to induce TNFα and IL-1β. At the same time, several parameters related to NO synthesis were measured at 3 h, 6 h and 24 h after C5b-9 stimulation. The effects of monoclonal antibodies against TNFα and IL-1β on NO synthesis were examined in this system. RESULTS: TNFα concentration in supernatant from MC in C5b-9 group was higher than that of control group at 6, 24 h after stimulation with C5b-9 complex and reversed by adding anti-TNFα McAb. C5b-9 complex didn't stimulate the release of IL-1β in same system. In addition, the expression of iNOS mRNA in MC was observed at 3 h after stimulation with C5b-9. Levels of iNOS mRNA expression and cGMP in MC and NO3-/NO2- in supernatant from MC in C5b-9 group were higher than those in control group at 6, 24 h after C5b-9 stimulation, these changes were also reversed by adding monoclonal antibody against TNFα. CONCLUSION: C5b-9 complex could induce iNOS mRNA expression at 3 h after C5b-9 stimulation, and the synthesis of NO at 6, 24 h was related to TNFα released from cultured MC of rats by C5b-9 complex to a certain extent.  相似文献   

16.
AIM: To observe free radicals (MDA, NO) and iNOS of patients with severe acute respiratory syndrome (SARS) and to explore its significance. METHODS: MDA, NO2-/NO3- and iNOS were determined in SARS patients during the early, recovery and follow-up stage, front doctors and nurses (contact group) and health people (health control). RESULTS: The level of MDA during first stage was higher than that of recovery stage and the MDA level of recovery stage was higher than that of follow-up stage, contact group, and health control group (P<0.01). The content of NO2-/NO3- during early stage was higher than that of other groups, and the NO2-/NO3- contents of recovery stage, follow-up stage were higher than that of contact group and health control group (P<0.01), respectively. The mean of iNOS during early stage was highest than that of other stages (P<0.01) and the mean of recovery stage was higher than that of contact group (P<0.05), there were no difference in iNOS activity among any other groups (P>0.05). CONCLUSION: The pathological injury in pathogenesis of SARS is related to free radicals.  相似文献   

17.
AIM: To investigate the protective effect of Ginkgo biloba extract (GBE) on diabetic testis and explore its possible mechanism. METHODS: Testicular structure of streptozotocin-induced diabetic rats was observed under light microscopy (LM) and transmission electron microscopy (TEM). Content of malondialdehyde (MDA), NO2-/NO3- and activity of superoxide dismutase (SOD), nitric oxide synthase (NOS) were determined in testicular homogenate. RESULTS: In diabetic rats, it was manifestated as deformation of seminiferous tubule, atrophy and shedding of germinal epithelium under LM, while expansion of smooth endoplasmic reticulum, formation of fatty vacuoles and decrease of lysosome obviously in the cytoplasm of sertoli cell under TEM, the injury of testicular tissue was improved by GBE. Compared with diabetic rats, activity of SOD increased while activity of tNOS and iNOS, content of MDA and NO2-/NO3- decreased in GBE-treated rats. CONCLUSION: GBE could effectively prevent the development of diabetic testis and the effect may be partly achieved by resisting lipid peroxidation,restraining the activity of testicular tissue iNOS and reducing the pathological alterations of NO.  相似文献   

18.
AIM: To investigate the preventive effect of PNS on chronic hypoxic pulmonary hypertension in rats. METHODS: Pulmonary arterial pressure observation, hematocrit (Hct)measurement, biochemical analysis and transmission electron microscopy were conducted to investigate the role of PNS. RESULTS: (1)Mean pulmonary arterial pressure (mPAP), right ventricular mean pressure (RVMP) and Hct were significantly higher in hypoxia group (H group) than that of control group (C group) and were much lower in hypoxia with PNS group (HT group) than that in H group; (2) Nitric oxide (NO2-/NO3-) concentration and nitric oxide synthase (NOS) activity in the plasma and the lung tissue, total superoxide dismutase (T-SOD) and copper/zinc-containing enzyme (Cu/ZnSOD) activities in the plasma were all significantly lower in H group than that in C group and were much higher in HT group than that in H group, but NO2-/NO3- concentration and NOS activity were still markedly decreased in comparison with C group; (3) Injury of endothelial cells in pulmonary arteriole was improved obviously in HT group Compared with H group. CONCLUSIONS: These results suggest that PNSreduces the increase in mPAP, probably through adjusting NOlevel, anti-damaging effectof free radicals, inhibiting the injury of endothelial cells and decreasing Hct.  相似文献   

19.
AIM:To observe the change of nitric oxide (NO) generation system in the vascular adventitia, media and intima in septic shock rats.METHODS:The septic shock model was made in rats by caecal ligation and puncture. The intima, media and adventitia of the rat aorta were separated. NO production (NO2-), nitric oxide synthase(NOS) activity and L-arginine (L-Arg) transport were measured, separately. Inducible NOS (iNOS) distribution was detected by immunohistochemistry.RESULTS:Both in early and late stage of septic shock, NO2- from the intima was decreased by 66.1% and 78.9%(P<0.01), while NO2- from the media was increased by 1.1 and 2.2 folds(P＜0.01), and the adventitia 9.6 and 18.6-fold (P＜0.01), as compared with the sham group, respectively. The changes of NOS activity and the L-arginine transport in the intima, the media layer and the adventitia of the aorta in the septic shock rat paralleled with that of NO2- in these tissues. The results of iNOS immunohistochemistry showed that there were obviously positive staining in the media layer and adventitia, especially the adventitia of the rat aortas in septic shock, as compared with that in the sham control.CONCLUSIONS:During septic shock, NO production in the aortic intima was progressively suppressed. However, it was progressively increased in the aortic medial layer and adventitia, especially the adventitia with shock processes. These changes result from different changes of L-arginine transport, NOS activity and its expression in three layers of the aorta from the septic shock rat.  相似文献   

20.
AIM:To observe the changes in nitric oxide(NO) and peroxynitrite anion (ONOO- ) in the injuried lung following the ischemia-reperfusion of hind limbs and evaluate the contribution of NO and ONOO- to tissue injury.METHODS:A model of hind limbs ischemia was made by clamping infrarenal aorta with a microvascular clip and lung injury occurring after reperfusion.Lung t issue was obtained from the animals received sham operation(group 1),4 hours ischemia without reperfusion(group2),1 hour reperfusion following 4 hours ischemia(group3)and 4 hours reperfusion fol owing 4 hours ischemia(group4).The contents of MDA,NO2-/NO3- and the activities of SOD in the lung were examined.Immunohistochemical echnique was used to determine the immunoreactivity to iNOS and nitrotyrosine(NT)-a specific "footprint" of peroxynitrite.RESULTS:Compared with group1 and group2,the contents of MDA and NO2-/NO3- increased significantly (P<0.05) and the activities of SOD decreased markedly(P＜0.05) in group3 and group4.Immunohistochemical examination demonstrated intense staining for iNOS and NT throughout the lung in group3 and group4.CONCLUSION:NO and ONOO- are involved in oxidant-mediated lung injury following reperfusion of ischemic hind limbs.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号