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 expression of matrix metalloproteinase-9 (MMP-9), its tissue inhibitor of matrix metalloproteinase (TIMP-1), inducible nitric oxide synthase (iNOS) and contents of nitric oxide (NO) in the ocular tissues of Sprague-Dawley (SD) rats with endotoxin induced uveitis（EIU）. Methods Ninety SD rats were randomly divided into experimental (81 rats) and control group (9 rats). The model of EIU was induced in rats in experimental group by injecting with lipoplysaccharide (LPS) 200 μl into the hind feet pads, while the rats in the control group were not injected. Nine rats were executed 0, 6, 12, 18, 24, 48, 72, 96 hours and 7 days, respectively, after injecting with LPS; the NO content and concentration of protein in the aqueous humor in blood plasma, aqueous humor, and uveal tissues were detected. The expressions of MMP-9, TIMP-1 and iNOS in the ocular tissues were detected by immunohistochemistry, and the average absorbance (A) value was evaluated by computer medical image analysis system. Results iNOS, MMP-9 and TIMP-1 expressed in the epithelial cells of iris and ciliary body and exudated inflammatory cells of rats. The concentration of protein in the aqueous humor, the contents of NO in blood plasma, aqueous humor, and uveal tissues, and A value of MMP-9 had obvious relativity with the inflammatory extent, while no positive correlation was found between the inflammatory extent and the A value of iNOS and TIMP-1. Expression of iNOS was found 6 hours after injection, reached the peak after 12 hours, and then dropped gradually. The expression of TIMP-1 could be seen 24 hours after injection, and reached its peak after 72 hours. Conclusion The content of NO and expressions of iNOS, MMP-9 and TIMP-1 changes from the beginning and during the development of EIU, which suggests that NO, iNOS, MMP-9 and TIMP-1 are involved in the pathologic process of EIU. (Chin J Ocul Fundus Dis, 2005, 21: 371-374)
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.
Objective To study the effect of various doses of estrogen on tissue injury, blood supply and survival area of skin flap and to investigate its mechanism. Methods Thirty New Zealand white rabbits aged 3-4 months old and weighing 1.5-2.2 kg (male or female) were used. Random pattern skin flap (12 cm × 3 cm in size) taking the central l ine of the rabbit dorsum as axis and with the pedicle attached at the proximal end was prepared, and the flap pedicle division was performed 7 days after operation. The rabbits were divided randomly into three groups (n=10 rabbits per group). At 2, 4, and 6 days after operation, the proximal edge of flap in group A and B received 100 ?g/kg and 50 ?g/kg subcutaneous injection ofestradiol benzoate, respectively, while group C received no further treatment serving as control group. General condition ofthe rabbits was observed after injection, gross observation was performed 3 and 7 days after injection, survival area of the skin flap was measured 7 days after injection, contents of malondialdehyde (MDA) and nitric oxide (NO) were tested 5 days after injection, and the flaps were harvested 4 and 7 days after injection to receive histology and no significant difference was noted between group A and group B (P gt; 0.05). The NEU counts 4 days after injection were (18.20 ±6.24) cells/HP in group A, (21.27 ± 5.34) cells/HP in group B, and (28.78 ± 7.92) cells/HP in group C, and at 7 days after injection, there were (15.16 ± 7.02) cells/HP in group A, (18.12 ± 6.44) cells/HP in group B, and (29.67 ± 9.12) cells/HP in group C. The VEGF score 4 days after injection was (4.02 ± 0.48) points in group A, (4.19 ± 0.66) points in group B and (3.67 ± 0.49) points in group C, and at 7 day after injection, it was (4.96 ± 0.69) points in group A, (5.12 ± 0.77) points in group B, and (3.81 ± 0.54) points in group C. Significant difference was evident between 4 days and 7 days after injection in group A or B in terms of NEU counts and VEGF score (P lt; 0.05), and difference between 4 days and 7 days after injection in group C was not significant (P gt; 0.05), and the differences among 3 groups were significant (P lt; 0.05). Conclusion Estrogen injection can increase VEGF expression and NO content of flap, decrease MDA content and NEU infiltration of flat, and improve survival area of flap.
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 observe the effects of nitric oxide ( NO) inhalation on lung inflammation of acute lung injury ( ALI) in rats. Methods Twenty-four SD rats were randomly divided into four groups, ie. a normal control group, an ALI group, a 20 ppm NO inhalation group, and a 100 ppm NO inhalation group. ALI model was established by LPS instillation intratracheally and the control group was instilled with normal saline. Then they were ventilated with normal air or NO at different levels, and sacrificed 6 hours later. Pathological changes were evaluated by HE staining. The expression of TLR4 in lung tissues was detected by immunohistochemistry. IL-6 level in lung homogenate was measured by ELISA. Results In the ALI group, the inflammation in bronchus and bronchioles was more apparently, and the expressions of TLR4and IL-6 were elevated significantly compared with the control group. 20 ppm NO inhalation significantly decreased the expression of TLR4 and IL-6, and alleviated the inflammation of ALI. However, 100 ppm NO inhalation did not change TLR4 expression and lung inflammation significantly, and increased IL-6 level.Conclusions Inhalation low level of NO( 20 ppm) can alleviate lung inflammation possibly by reducing theexpression of TLR4 and IL-6.
Objective To study the expression of inducible nitric oxide synthase (iNOS)，endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) in human gastric cancer and their relationship with tumor angiogenesis and to investigate the interaction of NOS and VEGF in gastric cancer. Methods The expression and distribution of VEGF, iNOS and eNOS in 34 gastric cancer specimens were detected with immunohistochemistry. Microvessel density (MVD) was counted with FⅧRAg immune specific staining. Results The expression rates of iNOS, eNOS and VEGF in 34 gastric cancers were 73.5%, 82.4% and 91.2% respectively. The expression of VEGF had a significant positive relation with iNOS, but not with eNOS. The MVDs of VEGF or iNOS positive gastric cancers were obviously higher than those of VEGF or iNOS negative gastric cancers. There was no significant difference between the MVDs of eNOS positive gastric cancers and eNOS negative ones. Conclusion MVD increases with increase of expression of VEGF and iNOS in gastric cancer. It is indicated that VEGF and iNOS can promote gastric cancer angiogenesis. VEGF and iNOS have a significant positive correlation, which suggests that in human gastric cancer, iNOS plays an important role in the production and action of VEGF.
Objective To observe the relationship between endothelial constitutive nitric oxide synthase (ecNOS) genetic polymorphism and diabetic retinopathy（DR）of non insulindependent diabetes mellitus (NIDDM) patients of the Han nationality.Methods A total of 166 patients who clinical diagnosed with NIDDM as case group, 85 cases of patients (cataract or fracture) and healthy subjects without diabetes, hypertension and kidney disease,over 40 years old of age and without consanguinity between each other were selected as normal control group. Case group were divided into non-DR (NDR) group, nonproliferative-DR (BDR) group and proliferativeDR (PDR) group according to the result of fundus fluorescein angiography. Case group and normal control group subjects all were Han nationality. DNA was extracted from peripheral venous blood; the fourth 27 base pairs (bp) repeat polymorphism of ecNOS gene by was measured by polymerase chain reaction (PCR). Results The 27 bp repeat sequences within the ecNOS gene present in the Han nationality,allele b repeat 5 times, alleles a repeat 4 times. PCR results showed that there are 2 alleles and 3 genotypes in normal control, NDR, BDR and PDR group. The frequency of genotype bb、ab、aa were 80%, 16.5%, 3.5% in normal subjects; 77.2％, 13.9%, 8.9％ in NDR group; 80.5％, 17.1%,2.4％ in BDR group;78.3％, 13%, 8.7％ in PDR group,respectively. The allele frequency (chi;2 =1.841) and gene frequency (chi;2=3.847) were not statistically significant (P＞0.5) in normal control,NDR,BDR and PDR group. Logistic regression analysis showed that there is no relation between DR and ecNOS duplicated gene polymorphism. Conclusions There is 27 bp repeated polymorphism in 4th intron of ecNOS gene, which may not be associated with the DR of NIDDM in the Han nationality.
ObjectiveTo explore the effect of hypertonic saline (HTS) pretreatment on levels of nitric oxide (NO) and endothelin-1(ET-1) and their correlation in hepatic ischemia reperfusion (HIR) injury in rats. MethodsThe HIR injury models were made by using Pringle, s maneuver in 45 healthy adult male Sprague-Dawley rats, which were randomly divided into three groups (n=15):sham operation (SO) group, HIR group, and HTS group. The animals were killed at 1, 6, and 24 h after reperfusion. The levels of serum NO and ET-1 were measured respectively, the correlation between NO level and ET-1 level at 6 h after reperfusion was analyzed. ResultsAt the time points of 1 h, 6 h, and 24 h after reperfusion, the serum NO levels in the HTS group and HIR group were all significantly lower than those in the SO group (P < 0.01), but the serum ET-1 levels were all significantly higher than those in the so group (P < 0.01). The serum NO levels at the time points of 1 h, 6 h, and 24 h in the HTS group were significantly higher than those at the same time in the HIR group (P < 0.01), but the serum ET-1 levels in the HTS group were significantly lower than those in the HIR group (P < 0.01). At all the time points, every detected goal had more marked level at the time point of 6 h after reperfusion. The NO level was negatively correlated with the ET-1 level. ConclusionsHTS could change levels of serum NO and ET-1 after HIR injury, and which has a negative correlation. Its mechanism might probably stimulate serum NO level and reduce the ET-1 level through some way so as to enable both dynamic balance to the benign development direction and achieve a protective effect.
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.