Objective The effects of endotoxin, cytokines, nitric oxide were reviewed in the development of hyperdynamic circulatory syndrome in portal hypertension. Methods Liceratures of overseas main studies in hyperdynamic circulatory syndrome of portal hypertension in recent 10 years were reviewed. Results The hyperdynamic circulatory syndrome was found in 30%-50% of patients with cirrhosis and in all animal models of portal hypertension. The research results of the effects of endotoxin, cytokines, nitric oxide in the development of hyperdynamic circulatory syndrome were different. Conclusion Hyperdynamic circulatory syndrome contribute to the maintenance and aggregation of portal hypertension. Endotoxin, cytokines, nitric oxide may play a role in the development of hyperdynamic circulatory syndrome. Nitric oxide is a more important factor. The effect of other factors is probably mediated by nitric oxide.
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)
ObjectiveTo investigate the relationship between the changes of nerve cells in sphincter of Oddi and acute pancreatitis. MethodsThe rabbit models of acute pancreatitis were prepared by using sodium taurocholate perfusion. Immunohistochemical method was used to detect the expressions of nitric oxide synthase (NOS) and vasoactive intestinal peptide (VIP) in neurons of the sphincter of Oddi. ResultsIn the control group, (45.83±2.17)% of myenteric neurons were NOS-positive, (52.46±2.47)% of myenteric neurons were VIP positive, and (22.73±1.95)% of myenteric neurons were NOS and VIP double positive. In contrast, (11.26±0.93)% of myenteric neurons were NOS-positive and (28.62±2.83)% of myenteric neurons were VIP positive in SAP group, which were significantly less than those of control group (P < 0.01). ConclusionsThe sphincter of Oddi of normal rabbits is rich in VIP and NOS positive neurons. The significant reduction of NOS-positive and VIP-positive neurons when SAP, which may be the reason of decreased the activities of the sphincter of Oddi.
ObjectiveTo compare the biological features of early and late endothelial progenitor cells (EPCs) by isolating and culturing early and late EPCs from the human peripheral blood so as to find some unique properties of EPCs and to propose a suitable strategy for EPCs identification. MethodsMononuclear cells were isolated from the human peripheral blood using density gradient centrifugation. Then, the cells were inoculated in human fibronectin-coated culture flasks and cultured in endothelial cell basal medium 2. After 4-7 days and 2-3 weeks culture, early and late EPCs were obtained respectively. The morphology, proliferation potential, surface markers, cytokine secretion, angiogenic ability, and nitric oxide (NO) release were compared between 2 types of EPCs. Meanwhile, the human aortic endothelial cells (HAECs) were used as positive control. ResultsThe morphology of early and late EPCs was different:early EPCs formed a cell cluster with a spindle shape after 4-7 days of culture, and late EPCs showed a cobblestone appearance. Late EPCs were characterized by high proliferation potential and were able to form capillary tubes on Matrigel, but early EPCs did not have this feature. Both types EPCs could ingest acetylated low density lipoprotein and combine with ulex europaeus Ⅰ. Flow cytometry analysis showed that early EPCs did not express CD34 and CD133, but expressed the CD14 and CD45 of the hematopoietic stem cell markers;however, late EPCs expressed CD31 and CD34 of the endothelial cell markers, but did not express CD14, CD45, and CD133. By RT-PCR analysis, the expressions of vascular endothelial growth receptor 2 and vascular endothelial cadherin in early EPCs were significantly lower than those in the late EPCs and HAECs (P<0.05), but no significant difference was found in the expression of von Willebrand factor and endothelial nitric oxide synthase (eNOS) between 2 type EPCs (P>0.05). The concentrations of vascular endothelial growth factor, granulocyte colony-stimulating factor, and interleukin 8 were significantly higher in the supernatant of early EPCs than late EPCs (P<0.05). Western blot assay indicated eNOS expressed in both types EPCs, while the expression of eNOS in late EPCs was significantly higher than early EPCs at 5 weeks (P<0.05). Both cell types could produce similar amount of NO (P>0.05). ConclusionThe expression of eNOS and the production of NO could be used as common biological features to identify EPCs, and the strategy of a combination of multiple methods for EPCs identification is more feasible.
Objective To study the effects of L-arginine （L-Arg） on cell proliferation, inducible nitric oxide synthase (iNOS) expression and cell cycle in human colon carcinoma cell line LS174 through nitric oxide (NO) pathway. Methods LS174 cells were cultured in medium with L-Arg at different concentrations for different times. MTT method was employed to evaluate the level of the cell proliferation. The production of NO in culture supernatants of LS174 cell was detected with enzyme reduction of nitrate. The distribution of the cell cycle was detected with the flow cytometry (FCM). The expression level of iNOS in the cells was determined by Western blot and SP immunocytochemical staining method. Results The growth of LS174 was promoted by the L-Arg at low concentration (0.125 mmol/L) and inhibited at high concentrations (0.5， 2， 8 and 32 mmol/L). The level of NO was increased with the increasing concentration of L-Arg in culture medium. To compare with the control group, the ratio of cells at S phase was increased after 48 hours’ treatments with high concentrations (0.5, 2, 8 and 32 mmol/L) of L-Arg (P＜0.05, P＜0.01); while there was no obvious difference after treatments with low concentration (0.125 mmol/L) of L-Arg (Pgt;0.05). With the increase of the concentration of L-Arg, the expression of iNOS was increased as compared with control group. The higher the concentration of L-Arg was, the better the effect. Conclusion L-Arg can induce the expression of iNOS resulting in increase the production of nitric oxide (NO). Low concentration of L-Arg can promote the growth of LS174 cells, while high concentration ones can inhibit growth and proliferation. The high concentration of L-Arg could induce S phase arrestion in the cell cycle.
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.
Objective To explore the effects of exogenous ubiquitin on lung injury and serum nitric oxide ( NO) level of mice in the early stage of sepsis induced by cecal ligation and perforation ( CLP) . Methods Seventy-seven mice were devided randomly into three groups, ie. CLP Group ( n =28) , SHAM Group ( n =28) and UB Group( n = 21) . Six hours after operation, seven mice of both Group CLP and SHAM were sacrificed for lung and blood sampling. Meanwhile all mice of Group UB were injected intravenously with exogenous ubiquitin of 10 mg/kg body weight. Seven mice of each group were sacrificed at seven, eight and nine hours after operation. Lung water content and serum level of nitrate /nitrite ( NO2 /NO3 , the stable end-products of NO) , were determined. Pathological changes of lung were compared among the groups. Results Lung water content of Group UB was lower than that of Group CLP at each observational time point. Futhermore, there was a significant differentce in lung water content between Group UB and CLP at 9 hours. Pathological examination revealed that inflammatory hyperemia and infiltration of pulmonary parenchyma reduced in Group UB, compared with Group CLP. Serum NO levels of Group CLP and UB were similar at each time point. Conclusions In the early stage of murine sepsis induced by CLP, a single introvenous bolus of exogenous ubiquitin significantly decreases lung capillary vascular permeability, and probably makes a temporal reduction of acute lung injury while it has no obvious effects on serumNO level.
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 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.
Objective To explore the effect and mechanism of ultrashort wave (USW) for prevention and treatment of vascular crisis after rat tail replantation. Methods Eighty 3-month old female Sprague Dawley rats (weighing 232.8-289.6 g) were randomly divided into 5 groups. In each group, based on the caudal vein and the coccyx was retained, the tail was cut off. The tail artery was ligated in group A; the tail artery was anastomosed in groups B, C, D, and E to establish the tail replantation model. After surgery, the rats of group B were given normal management; the rats of group C were immediately given intraperitoneal injection (3.125 mL/kg) of diluted papaverine hydrochloride injection (1 mg/mL); the rats of groups D and E were immediately given the local USW treatment (once a day) at anastomotic site for 5 days at the dosage of 3 files and 50 mA for 20 minutes (group D) and 2 files and 28 mA for 20 minutes (group E). The survival rate of the rat tails was observed for 10 days after the tail replantation. The tail skin temperature difference between proximal and distal anastomosis was measured at pre- and post-operation; the change between postoperative and preoperative temperature difference was calculated. The blood plasma specimens were collected from the inner canthus before operation and from the tip of the tail at 8 hours after operation to measure the content of nitric oxide (NO). Results The survival rates of the rat tails were 0 (0/14), 36.4% (8/22), 57.1% (8/14), 22.2% (4/18), and 75.0% (9/12) in groups A, B, C, D, and E, respectively, showing significant overall differences among 5 groups (χ2=19.935, P=0.001); the survival rate of group E was significantly higher than that of group B at 7 days (P lt; 0.05), but no significant difference was found between the other groups by pairwise comparison (P gt; 0.05). At preoperation, there was no significant difference in tail skin temperature difference among 5 groups (P gt; 0.05); at 8 hours, 5 days, 6 days, and 7 days after operation, significant overall difference was found in the change of the skin temperature difference among groups (P lt; 0.05); pairwise comparison showed significant differences after operation (P lt; 0.05): group B gt; group D at 8 hours, group C gt; group D at 5 days, groups A, B, and C gt; group D at 6 days, groups B and C gt; groups A and E, and group B gt; group D at 7 days; but no significant difference was found between the other groups at the other time points (P gt; 0.05). Preoperative plasma NO content between each group had no significant difference (P gt; 0.05). The overall differences had significance in the NO content at postopoerative 8 hours and in the change of the NO content at pre- and post-operation among groups (P lt; 0.05). Significant differences were found by pairwise comparison (P lt; 0.05): group D gt; groups A, B, and C in the plasma NO content, group D gt; groups A and B in the change of the NO content at pre- and post-operation; but no significant difference was found between the other groups by pairwise comparison (P gt; 0.05). Conclusion Rat tail replantation model in this experiment is feasible. USW therapy can increase the survival rate of replanted rat tails, reduce skin temperature at 7 days, improve blood supply, increase the content of nitric oxide at the early period and prevent vascular crisis.