Attenuation of Nitric Oxide Synthase Gene Expression in Rat Lung Induced by Hypoxia

In order to investigate the role of nitric oxide(NO) in pathogenesis of hypoxic pulmonary hypertension(HPH), the mean pulmonary arterial pressure(mPAP), mRNA expression of NO synthase(NOS) in lung tissues, cGMP levels, and their relationships were studied in rats exposed to hypoxia from 8 h to 28days. The results showed that mPAP began to increase in animals exposed to 10 % O2 for 8 h. Moreover, the longer the exposure, the higher the mPAP.Northern blot analysis and dot blot hybridization indicated that mRNA expression of NO in lung tissues of hypoxic rats tended to decrease with exposure days, but that of β-actin which acted as a control did not alter. The cGMP levels of plasma and lung tissues in hypoxic rats also inclined to be lower with exposure days. A marked negative correlations between the changes of cGMP levels and those of mPAP were found. It was suggested that mRNA expression of NOS gene was attenuated in hypoxic lung tissues, which may be one of important pathogenetic mechanisms of HPH.

EFFECT OF TNF-a AND IFN-g ON THE EXPRESSION OF INDUCIBLE NITRIC OXIDE SYNTHASE GENE AND PROLIFERATION INHIBITION OF HUMAN COLON CANCER CELL LINE

Objective: To study the expression of the inducible nitric oxide synthase (iNOS) gene and the effects of tumor necrosis factor-α(TNF-a) and interferon-γ(IFN-g)on proliferation of the continuous cultured human colon cancer cell line CCL229. Methods: Using the molecular and biochemical techniques and electron microscopy to analyze the expression of iNOS, production of NO and growth characteristics of human colon cancer cells. Results: cytokine treatment can induce expression of the iNOS gene and production of nitric oxide was significantly higher after treatment of CCL229 cells with TNF-αor IFN-γ. Treatment with either cytokine or a combination of both significantly increased levels of Malondialdehyde (MDA) over control. Furthermore, cytokine treatment increased the proliferation inhibition rate as assessed in vitro and decreased the cell proliferation index on flow cytometry. Electron microscopy showed that cells treated with cytokines had fewer pseudopodia or cell processes than control cells and that cytokine treated cells had dilatation of the mitochondria and endoplasmic reticulum and dilated vesicular or tubular cisternae. Conclusion: Our findings indicate that TNF-α and IFN-γ induce the expression of iNOS gene in CCL229 cells, which increases the production of nitric oxide, inhibits proliferation, causes lipid peroxidation, and results in ultrastructural changes.

EFFECT OF RADIX SALVIAE MILTIORRHIZAE ON THE GENE EXPRESSION OF NITRIC OXIDE SYNTHASE IN ISCHEMIC RAT BRAINS

The effect of Radix Salviae Miltiorrhizae (RSM) on the gene expression of nitric oxide synthase (NOS) in rat brains during ischemia was studied with in situ hybridization and the results were analyzed with IBAS 2000 Image Analysis System. It was found that NOS gene expression of cerebral cortex and caudate-putamen was markedly increased in 24 hours in ischemia group (P

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic rate.However,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia patients.Similarly in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive decline.Nitric oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous system.Recently,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular dementia.This review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular dementia.Additionally,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

Neuronal nitric oxide synthase/reactive oxygen species pathway is involved in apoptosis and pyroptosis in epilepsy

Dysfunction of neuronal nitric oxide synthase contributes to neurotoxicity,which triggers cell death in various neuropathological diseases,including epilepsy.Studies have shown that inhibition of neuronal nitric oxide synthase activity increases the epilepsy threshold,that is,has an anticonvulsant effect.However,the exact role and potential mechanism of neuronal nitric oxide synthase in seizures are still unclear.In this study,we performed RNA sequencing,functional enrichment analysis,and weighted gene coexpression network analysis of the hippocampus of tremor rats,a rat model of genetic epilepsy.We found damaged hippocampal mitochondria and abnormal succinate dehydrogenase level and Na+-K+-ATPase activity.In addition,we used a pilocarpine-induced N2a cell model to mimic epileptic injury.After application of neuronal nitric oxide synthase inhibitor 7-nitroindazole,changes in malondialdehyde,lactate dehydrogenase and superoxide dismutase,which are associated with oxidative stress,were reversed,and the increase in reactive oxygen species level was reversed by 7-nitroindazole or reactive oxygen species inhibitor N-acetylcysteine.Application of 7-nitroindazole or N-acetylcysteine downregulated the expression of caspase-3 and cytochrome c and reversed the apoptosis of epileptic cells.Furthermore,7-nitroindazole or N-acetylcysteine downregulated the abnormally high expression of NLRP3,gasdermin-D,interleukin-1βand interleukin-18.This indicated that 7-nitroindazole and N-acetylcysteine each reversed epileptic cell death.Taken together,our findings suggest that the neuronal nitric oxide synthase/reactive oxygen species pathway is involved in pyroptosis of epileptic cells,and inhibiting neuronal nitric oxide synthase activity or its induced oxidative stress may play a neuroprotective role in epilepsy.

Nitric oxide synthase and heme oxygenase expressions in human liver cirrhosis

AIM： Portal hypertension is a common complication of liver cirrhosis. Intrahepatic pressure can be elevated in several ways. Abnormal architecture affecting the vasculature, an increase in vasoconstrictors and increased circulation from the splanchnic viscera into the portal system may all contribute. It follows that endogenous vasodilators may be able to alleviate the hypertension. We therefore aimed to investigate the levels of endogenous vasodilators, nitric oxide （NO） and carbon monoxide （CO） through the expression of nitric oxide synthase （NOS） and heme oxygenase （HO）. METHOD： Cirrhotic （n = 20） and non-cirrhotic （n = 20） livers were obtained from patients who had undergone surgery. The mRNA and protein expressions of the various isoforms of NOS and HO were examined using competitive PCR, Western Blot and immunohistochemistry. RESULTS： There was no significant change in either inducible NOS （iNOS） or neuronal NOS （nNOS） expressions while endothelial NOS （eNOS） was up- regulated in cirrhotic livers. Concomitantly, caveolin-1, an established down-regulator of eNOS, was upregulated. Inducible HO-1 and constitutive HO-2 were found to show increased expression in cirrhotic livers albeit in different Iocalizations. CONCLUSION： The differences of NOS expression might be due to their differing roles in maintaining liver homeostasis and/or involvement in the pathology of cirrhosis. Sheer stress within the hypertensive liver may induce increased expression of eNOS. In turn, caveolin-1 is also increased. Whether this serves as a defense mechanism against further cirrhosis or is a consequence of cirrhosis, is yet unknown. The elevated expression of HO-1 and HO-2 suggest that CO may compensate in its role as a vasodilator albeit weakly. It is possible that CO and NO have parallel or coordinated functions within the liver and may work antagonistically in the pathophysiology of portal hypertension.

Expression of inducible nitric oxide synthase and cyclooxygenase-2 in pancreatic adenocarcinoma:Correlation with microvessel density

AIM:Cydooxygenases (COX) are key enzymes for conversion of arachidonic acid to prostaglandins.Nitric oxide synthase (NOS) is the enzyme responsible for formation of nitric oxide. Both have constitutive and inducible isoforms.The inducible isoforms (iNOS and COX-2) are of great interest as regulators of tumor angiogenesis,tumorigenesis and inflammatory processes.This study was to clarify their role in pancreatic adenocarcinomas. METHODS:We investigated the immunohistochemical iNOS and COX-2 expression in 40 pancreatic ductal adenocardnomas of different grade and stage.The results were compared with microvessel density and dinicopathological data. RESULTS:Twenty-one (52.5%) of the cases showed iNOS expression,15 (37.5%) of the cases were positive for COX-2. The immunoreaction was heterogeneously distributed within the tumors.Staining intensity was different between the tumors.No correlation between iNOS and COX-2 expression was seen.There was no relationship with microvessel density. However,iNOS positive tumors developed more often distant metastases and the more malignant tumors showed a higher COX-2 expression.There was no correlation with other clinicopathological data. CONCLUSION:Approximately half of the cases expressed iNOS and COX-2.These two enzymes do not seem to be the key step in angiogenesis or carcinogenesis of pancreatic adenocarcinomas.Due to a low prevalence of COX-2 expression,chemoprevention of pancreatic carcinomas by COX-2 inhibitors can only achieve a limited success.

Endothelial Nitric Oxide Synthase Gene Polymorphisms Associated with Susceptibility to High Altitude Pulmonary Edema in Chinese Railway Construction Workers at Qinghai-Tibet over 4500 Meters above Sea Level

Objective To examine whether the polymorphisms of endothelial nitric oxide synthase (eNOS) gene are associated with the susceptibility to high altitude pulmonary edema (HAPE) in Chinese railway construction workers at Qinghai-Tibet where the altitude is over 4 500 m above sea level. Methods A case-control study was conducted including 149 HAPE patients in the construction workers and 160 healthy controls randomly recruited from their co-workers, matching the patients in ethnicity, age, sex, lifestyle, and working conditions. Three polymorphisms of eNOS gene, T-786C in promoter, 894G/T in exon 7, and 27bp variable number tandem repeat (VNTR) in intron 4, were genotyped using polymerase chain reaction (PCR) and confirmed with DNA sequencing. Results The frequencies of 894T allele and heterozygous G/T of the 894G/T variant were significantly higher in HAPE patients group than in the control group (P=0.0028 and P=0.0047, respectively). However, the frequencies of the T-786C in promoter and the 27bp VNTR in intron 4 were not significantly different between the two groups. Haplotypic analysis revealed that the frequencies of two haplotypes (H3,T-T-b, b indicates 5 repeats of 27 bp VNTR; H6, C-G-a, a indicates 4 repeats of 27 bp VNTR) were significantly higher in HAPE patients (both P<0.0001). On the contrary, the frequencies of H1 (T-G-b) and H2 (T-G-a) were lower in HAPE patients than in healthy controls (both P<0.001). Conclusions Two haplotypes (T-T-b and C-G-a) may be strongly associated with susceptibility to HAPE. Compared with the individual alleles of eNOS gene, the interaction of multiple genetic markers within a haplotype may be a major determinant for the susceptibility to HAPE.

Effect of warm acupuncture on nitric oxide synthase and calcitonin gene-related peptide in a rat model of lumbar nerve root compression

BACKGROUND： Varying degrees of inflammatory responses occur during lumbar nerve root compression. Studies have shown that nitric oxide synthase （NOS） and calcitonin gene-related peptide （CGRP） are involved in secondary disc inflammation. OBJECTIVE： To observe the effects of warm acupuncture on the ultrastructure of inflammatory mediators in a rat model of lumbar nerve root compression, including NOS and CGRP contents. DESIGN, TIME AND SETTING： Randomized, controlled study, with molecular biological analysis, was performed at the Experimental Center, Sixth People＇s Hospital Affiliated to Shanghai Jiao Tong University, between September 2006 and April 2007. MATERIALS： Acupuncture needles and refined Moxa grains were purchased from Shanghai Taicheng Technology Development Co., Ltd., China; Mobic tablets were purchased from Shanghai Boehringer Ingelheim Pharmaceuticals Co., Ltd., China; enzyme linked immunosorbent assay （ELISA） kits for NOS and CGRP were purchased from ADL Biotechnology, Inc., USA. METHODS： A total of 50, healthy, adult Sprague-Dawley rats, were randomly divided into five groups normal, model, warm acupuncture, acupuncture, and drug, with 10 rats in each group. Rats in the four groups, excluding the normal group, were used to establish models of lumbar nerve root compression. After 3 days, Jiaji points were set using reinforcing-reducing manipulation in the warm acupuncture group. Moxa grains were burned on each needle, with 2 grains each daily. The acupuncture group was the same as the warm acupuncture group, with the exception of non-moxibustion. Mobic suspension （3.75 mg/kg） was used in the oral drug group, once a day. Treatment of each group lasted for 14 consecutive days. Modeling and medication were not performed in the normal group. MAIN OUTCOME MEASURES： The ultrastructure of damaged nerve roots was observed with transmission electron microscopy; NOS and CGRP contents were measured using ELISA. RESULTS： The changes of the radicular ultramicrostructure were characterized by Wallerian degeneration; nerve fibers were clearly demyelinated; axons collapsed or degenerated; outer Schwann cell cytoplasm was swollen and its nucleus was compacted. Compared with the normal group, NOS and CGRP contents in the nerve root compression zone in the model group were significantly increased （P 〈 0.01）. Nerve root edema was improved in the drug, acupuncture and the warm acupuncture groups over the model group. NOS and CGRP expressions were also decreased with the warm acupuncture group having the lowest concentration （P 〈 0.01）. CONCLUSION： In comparison to the known effects of Mobic drug and acupuncture treatments, the warm acupuncture significantly decreased NOS and CGRP expression which helped improve the ultrastructure of the compressed nerve root.

Effects of Infrasound on Gastric Motility, Gastric Morphology and Expression of Nitric Oxide Synthase in Rat

Infrasound widely condition, productive exists in nature, our living and traffic environment. Gastrointestinal tract is relatively sensitive to infrasound. However, the effect of infrasound on gastrointestinal function is unclear. Therefore, the purpose of our study was to observe the effects of infrasound on gastric motiliW and gastric morphology and to assess the expression of nitric oxide synthase （NOS） in gastric antrum after exposure to infrasound of 8 Hz - 130 dB for 2 hours per day for 14 consecutive days. Gastric motility was assessed by gastric fluid-emptying rate. Gastric morphology was evaluated by HE. The expression of NOS was measured by tissue microarray technology. The results would contribute to understand the role of infrasound in gastroenterology, and help to explain the mechanism of infrasound on gastroenterology.

Effects of melatonin on learning abilities, cholinergic fibers and nitric oxide synthase expression in rat cerebral cortex

BACKGROUND: Melatonin is a kind of hormones derived from pineal gland. Recent researches demonstrate that melatonin is characterized by anti-oxidation, anti-senility and destroying free radicals. While, effect and pathogenesis of pineal gland on learning ability should be further studied. OBJECTIVE: To investigate the effects of pinealectomy on learning abiliy, distribution of cholinesterase and expression of neuronal nitric oxide synthase (nNOS) in cerebral cortex of rats and probe into the effect of melatonin on learning ability, central cholinergic system and nNOS expression. DESIGN: Randomized grouping design and animal study. SETTING: Department of Neurology, the 187 Hospital of Chinese PLA. MATERIALS: A total of 12 male SD rats, of normal learning ability testing with Y-tape maze, of clean grade, weighing 190-210 g, aged 6 weeks, were selected in this study. METHODS: The experiment was carried out in the Department of Neurology, Zhujiang Hospital from July 1997 to June 2000. All SD rats were divided into experimental group (n =6, pinealectomy) and control group (n =6, sham operation). Seven days later, rats in both two groups were continuously fed for 33 days. ① Learning ability test: The learning ability of rats was tested by trisection Y-type maze and figured as attempting times. ② Expression of acetylcholinesterase (AchE) was detected by enzyme histochemistry and nNOS was measured by SABC method. ③ Quantitative analysis of AchE fibers: AchE fibers density in unit area (surface density) was surveyed with Leica Diaplan microscope and Leica Quantimet 500+ image analytic apparatus and quantitative parameter was set up for AchE fibers covering density (μm2) per 374 693.656 μm2, moreover, the AchE fibers density was measured in Ⅱ-Ⅳ layers of motor and somatosensory cortex (showing three layers per field of vision at one time), in radiative, lacunaria and molecular layers of CA1, CA2 and CA3 areas, and in lamina multiforms of dentate gyrus. Three tissue slices were picked up randomly in the same part of each rat, together six tissue slices for nNOS expression and four near view (× 400) were selected in the parts of right neocortex, medial septal nucleus-diagonal band nucleus (SM-DB), corpus striatus and hippocampus to count nNOS-positive cells. MAIN OUTCOME MEASURES: Learning ability; distribution and quantitative analysis of AchE fibers; expression of nNOS in various cerebral areas. RESULTS: The twelve rats were all involved in the final analysis. ① Learning ability test: The learning abilities before operation in the experimental group [(14.67±4.97) times] were consistent with those in the control group [(14.33±4.32) times, P > 0.05], the learning abilities in the experimental group at 40 days after pinealectomy [(28.67±2.42) times] were obviously more than those before pinealectomy and those in the control group after operation [(13.83±8.33) times, P < 0.01]. ② Results of AchE-positive fibers density in cerebral cortex of rats: The AChE-positive fibers densities in motor and somatosensory cortex, CA1, CA2 and CA3 areas of hippocampus and in lamina multiforms of dentate gyrus in the experimental group were obviously lower than those in the control group [experimental group: (15 244±1 339), (14 764±1 391), (12 991±970), (15 077±1 020), (19 546±1 489), (19 337±1 378) μm2; control group: (21 001±1 021), (17 930±2 225), (17 260±1 342), (18 911±1 048), (24 108±1 671), (22 917±1 909) μm2, P < 0.01]. ③ Expression of nNOS in various cerebral areas: nNOS-positive cells in cerebral cortex of rats of the experimental group were more, furthermore the ones in somatosensory cortex were slightly more in motor cortex and the number (5.90±0.68) was more than that in the control group (3.68±0.39,P < 0.05). The nNOS-positive cells in SM-DB (16.21±2.03) were markedly more than those in the control group (9.32±1.05,P < 0.01). The nNOS-positive cells in hippocampus (4.27±0.75) and in corpus striatus (9.35±2.58) were not different with those in the control group (3.94±0.53, 8.96±2.31, P > 0.05). CONCLUSION: Decrease of melatonin due to pinealectomy of rats can result in learning disorder, which may be related to trauma of cholinergic neuron in cerebral cortex which were caused by nitric oxide neurotoxicity arose from the overexpression of nNOS in cerebral neocortex and SM-DB.

Expression of nitric oxide synthase in the spinal cord after selective brachial plexus injury

BACKGROUND: Some researches showed that motoneurons in spinal cord anterior horn wound die following brachial plexus injury, but the concrete mechanism of motoneurons death remains unclear. OBJECTIVE: To observe the expression of nitric oxide synthase (NOS) and survival of C7 motoneurons in spinal cord of rats after selective brachial plexus injury. DESIGN: A randomized controlled animal experiment. SETTING:Department of Anatomy, Sun Yet-sen Medical College, Sun Yet-sen University. MATERIALS: Totally 35 adult healthy male Sprague-Dawley rats with the body mass of 200-300 g were provided by Experimental Animal Center, Sun Yet-sen Medical College, Sun Yat-sen University. The rats were divided into control group (n =5) and experimental group(n =30) by random number table method, and the experimental group was divided into three injury subgroups: anterior root avulsion group, dorsal root transection group and spinal cord hemisection group, 10 rats in each group. There were horse anti-neuronal NOS (nNOS) polycolonal antibody (Sigma company) and nicotina mideadeninedinucleotide phosphate (NADPH-d) (Sigma Company). METHODS: The experiment was performed at Department of Anatomy, Sun Yet-sen Medical College, Sun Yet-sen University between September 2004 and April 2005. ①After anesthetizing the rats, the spinous process of second thoracic vertebra as a marker, the vertebra was exposed from C5 to T1 and the lamina of vertebra was unclenched, and spinal dura mater was carved to expose the spinal nerve dorsal roots of C5-T1. The right ventral root of C7 was avulsed, and the residual root was removed in anterior root avulsion group. The right ventral root of C7 was avulsed and the right dorsal roots of brachial plexus (C5-T1) were cut off in dorsal root transection group. In spinal cord hemisection group, the hemisection between the C5 and C6 spinal segment on right side and avulsion of right ventral root of C7 were made. In the control group, the vertebra from C5 to T1 was unclenched and the skin of wound was sutured. ②Three weeks after operation, behavior of rats was observed. The rats were killed after anesthesia. The C7 segment of spinal cord was removed and treated with NADPH-d staining, neutral red counterstaining and NOS immunohistochemistry staining to detect the expression of NOS. MAIN OUTCOME MEASURES: The expression of NOS and survival of C7 motoneurons in spinal cord of rats 3 weeks after operation. RESULTS: Among the 35 included rats, 3 rats died 2 weeks following operation, so totally 32 rats were involved in the result analysis. ①NADPH-d positive neurons of in anterior horn of C7 in the three groups: The NADPH-d positive neurons could be found in anterior horn of C7 in the three groups. The percentage of that in anterior root avulsion group to that of non-injury side of spinal cord was(20.98±2.65)%, (29.43±6.81)% in dorsal root transection group and (31.74±6.80)% in spinal cord hemisection group. There was significant difference among the three injury groups(F =5.135,P =0.016). There was significant difference in anterior root avulsion group with dorsal root transection group and spinal cord hemisection group (t =2.562,3.167,P < 0.05). There was no significant difference between the dorsal root transection group and spinal cord hemisection group (P =0.534). ②survival rate of motoneurons in anterior horn of C7: There were dead motoneurons in the three injury groups, the percentages of surviving motoneurons to that of non-injured side of spinal cord were (69.22±4.04)%,(62.01±3.82)% and (56.74±6.86)%, respectively. There were significant differences among the three groups (F =9.508,P =0.002). The anterior root avulsion group was significantly different from the other two groups(t =2.764,4.587,P < 0.05). There was no significant difference between the dorsal root transection group and spinal cord hemisection group(P =0.073). CONCLUSION: The selective brachial plexus injury can induce the up-regulation of NOS expression in motorneurons of spinal cord anterior horn and block descending pathway of cortex to cause the more significant up-regulation of NOS and low survival rate in motoneurons. It indicates that descending pathway of cortex can inhibit the NOS expression in motorneurons of spinal cord anterior horn, and the high NOS expression might induce the death of motorneurons in spinal cord anterior horn.

Research Progress on Inducible Nitric Oxide Synthase in the Pathogenesis of Pancreatic Malignancy

Pancreatic cancer is a common tumor of the digestive system.At present,the pathogenesis is still unclear,but current research on inducible nitric oxide synthase in relation to the pathogenesis of pancreatic malignant tumors is particularly extensive.Therefore,this article focuses on the research progress on inducible nitric oxide synthase in the pathogenesis of pancreatic cancer.

A Review on the Research Progress of Inducible Nitric Oxide Synthase in the Pathogenesis of Pancreatic Malignancy

Pancreatic cancer is a common tumor of the digestive system,at present,the pathogenesis is still unclear,but in the current research on the pathogenesis of pancreatic malignant tumors,the research on inducible nitric oxide synthase is particularly extensive.Therefore,this article focuses on the research progress of inducible nitric oxide synthase in the pathogenesis of pancreatic cancer.This is a review.

Effect of stellate block on vasomotor factor, vascular endothelial nitricoxide synthase and pulmonary arterial pressure in rabbits with hypoxic pulmonary artery hypertension

BACKGROUND： At present, inhalation of nitrogen monoxidum （NO） or other angiotenic is widely used to cure hypoxic pulmonary artery hypertension. In addition, recent researches demonstrate that postganglionic fiber of stellate ganglion can regulate contents of blood vessel endothelium-calcitonin gene-related peptide （BVE-CGRP） and nitricoxide synthase （NOS） in lung tissue. Therefore, stellate ganglion which is blocked with the local anesthetic may cause therapeutic effects on hypoxic pulmonary artery hypertension. OBJECTIVE： To observe the effects of stellate block on calcitonin gene-related peptide （CGRP） of vasodilation factors, prostacyclin, endothelin-i of vasoconstriction factors, thromboxan, blood vessel endothelium-nitricoxide synthase （BVE-NOS） and mean arterial pressure of lung tissue in rabbits with hypoxic pulmonary artery hypertension. DESIGN： Randomly controlled animal study. SETTING： Neurological Institute of Taihe Hospital Affiliated to Yunyang Medical College. MATERIALS： A total of 24 adult Japanese rabbits of both genders and weighing 2.3 - 2.6 kg were provided by Animal Experimental Center of Hubei Academy of Medical Science. SP kit was provided by Beijing Zhongshan Biotechnology Co., Ltd.; moreover, kits of endothelin-1, CGRP, prostacyclin and thromboxan were provided by Radioimmunity Institute, Scientific and Technological Developing Center, General Hospital of Chinese PLA, and color image analytical system （Leica-Q500IW） was made in Germany. METHODS：The experiment was carried out in the Neurological Institute of Taihe Hospital affiliated to Yunyang Medical College from February to December 2002. ① Rabbits were performed with aseptic manipulation to exposure left stellate ganglion and then it was put in epidural catheter for 1 week. In addition, one end of epidural catheter was fixed near by stellate ganglion and the other end was fixed through dorsal neck. All rabbits were randomly divided into 4 groups, including normal control group, stellate block group, hypoxia group and hypoxia ＋ stellate block group, with 6 in each group. Rabbits in the normal control group were perfused with saline through epidural catheter with 0.5 mL once for three times per day and 3 successive days in total; in addition, rabbits in the stellate block group were perfused with 2.5 g/L bupivacaine through epidural catheter with 0.5 mL once for three times per day and 3 successive days in total. Rabbits in the hypoxia group were used to establish hypoxic pulmonary artery hypertension models. That was to say, the experimental rabbits were put in hypoxic box （containing sodalime and calcium chloride to absorb CO2 and water） and given various flows of oxygen and nitrogen through the two lateral wells simultaneously. And then, oxygen was monitored with oxygen-concentration monitoring device to control the concentration in （10±2）% for 8 hours per day and 2 successive weeks in total. Rabbits in the hypoxia ＋ stellate block group were used to establish hypoxia models as the same as those in the hypoxia group. Two weeks later, 2.5 g,/L bupivacaine was pushed into epidural catheter with 0.5 mL once for three times per day and 3 successive days in total. Breast was directly opened to measure mean pulmonary artery pressure.② 6 mL blood was collected through pulmonary arterial duct to measure levels of plasma CGRP, prostacyclin, endothelin-I and thromboxane with radio-immunity technique; meanwhile, immunohistochemical staining was used to observe the changes of BVE-NOS content of the experimental rabbits in all groups. MAIN OUTCOME MEASURES： Changes of CGRP, prostacyclin, endothelin-1 and thromboxane and BVE-NOS. RESULTS： A total of 24 experimental rabbits were involved in the final analysis. ①As compared with those in the normal control group, hypoxic pulmonary artery hypertension of the experimental rabbits was higher in the hypoxia group and hypoxia ＋ stellate block group after hypoxia [（3.8±0.30）, （3.16±0.45）, （2.60± 0.27） kPa, P 〈 0.05, 0.01]; CGRP was lower [（68.20 ±8.78）, （108.24 ±14.35）, （130.25 ±22.70） ng/L, P 〈 0.05, 0.01]; prostacyclin was lower [（94.45± 10.68）, （98.77± 12.31）, （155.27±20.67） ng/L, P 〈 0.01]; endothelin-1 was higher [（184.7±29.66）, （115.27± 13.62）, （98.20±11.52）, ng/L, P 〈 0.05, 0.01]; thromboxan was higher [（226.27 ±30.46）, （207.67 ±27.32）, （124.25 ± 16.89） ng/L, P 〈 0.01 ]. As compared with that in hypoxia group, hypoxic pulmonary artery hypertension was decreased in hypoxia ＋ stellate block group （P 〈 0.05）, CGRP was increased （P 〈 0.01）, and endothelin-1 was decreased remarkably （P 〈 0.05）. ② Level of BVE-NOS of the experimental rabbits was higher in stellate block group, hypoxia group and hypoxia ＋ stellate block group than that in the normal control group [（0.25±0.06）, （0.27±0.07）, （0.46± 0.12）, （0.14±0.03）, P 〈 0.05], and NOS level was higher in the hypoxia ＋ stellate block group than that in hypoxia group （P 〈 0.05）. CONCLUSION： Mean arterial pressure is decreased in rabbits with hypoxic pulmonary artery hypertension after stellate block and level of endothelin-1 is also decreased; however, levels of CGRP and NOS are increased respectively.

Nitric oxide synthase gene expression in injured spinal cord tissue

OBJECTIVE: To investigate gene expression of three nitric oxide synthase isozymes in injured spinal cord tissue. METHODS: Thirty-six adult SD rats were randomly divided into six groups: a normal group and five injury groups, with six per each group. Animals in the injury groups were sacrificed at 2, 6, 12, 24, 48 h after injury. A compression injury model on the spinal cord was made according to Nystrom B et al and gene expression of the three NOS isozymes were examined by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Gene expression of nNOS and eNOS were detectable in the normal group and were up-regulated quickly after injury, reaching a maximum at 6 h: (0.633 +/- 0.012) and (1.236 +/- 0.207). Gene expression of iNOS was detectable only in the injury groups and it was gradually up-regulated after injury, reaching a maximum at 24 h: (1.043 +/- 0.049). CONCLUSION: Injury to the spinal cord leads to early up-regulation of cNOS and late up-regulation of iNOS. Different NOS isozymes may play different roles in secondary spinal cord injury.

Gene expression of two kinds of constitutive nitric oxide synthase in injured spinal cord tissue

Objective: To investigate the gene expression of two kinds of constitutive nitric oxide synthase (cNOS): neuronal NOS (nNOS) and endothelial NOS (eNOS) in injured spinal cord tissue. Methods: Thirty-six adult Sprague-Dawley rats were divided randomly into six groups: the normal group and the injury groups (2, 6, 12, 24, 48 h after injury, respectively). A compression injury model of the spinal cord was made and gene expression of nNOS and eNOS were examined by reverse transcription polymerase chain reaction (RT-PCR). Results: The gene expression of nNOS and eNOS was detected in the normal group and they were up-regulated quickly after injury, reaching the maximum at 6 h. There was no difference between gene expression of nNOS and eNOS in the normal group, but in each injury group the gene expression of eNOS was much higher than that of nNOS. Conclusions: Expression of constitutive NOS (cNOS) in spinal cord tissue was up-regulated after injury mainly in the early stage. cNOS as a whole offers protection in spinal cord injury, but different cNOS may play different roles.

Gene expression of inducible nitric oxide synthase in injured spinal cord tissue

Objective: To investigate gene expression of inducible nitric oxide synthase (iNOS) in injured spinal cord tissue of rats. Methods: Thirty-six adult Sprague-Dawley rats were divided randomly into six groups: a normal group and five injury groups, six animals in each group. Animals in the injury groups were killed at 2, 6, 12, 24, 48 hours after injury, respectively. A compression injury model of spinal cord was established according to Nystrom B et al, and gene expression of iNOS in spinal cord tissue was examined by means of reverse transcription polymerase chain reaction (RT-PCR). Results: Gene expression of iNOS was not detectable in normal spinal cord tissue but was seen in the injury groups. The expression was gradually up-regulated, reaching the maximum at 24 hours. The expression at 48 hours began to decrease but was still significantly higher than that at 2 hours. Conclusions: iNOS is not involved in the normal physiological activities of spinal cord. Expression of iNOS is up-regulated in spinal cord tissue in response to injury and the up-regulation exists mainly in the late stage after injury. Over-expression of iNOS may contribute to the late injury of spinal cord.

NOS3、IL-1β基因多态性与不明原因复发性流产相关性的研究进展

不明原因复发性流产(URSA)是妇产科中最常见的妊娠并发症之一,给患者身心和家庭造成严重的负面影响,是育龄期女性生殖健康的一大威胁。其病因及发病机制不清,尚无有效的防治措施,是当前生殖健康领域的一大难点。有研究表明一氧化氮合酶3(NOS3)、白介素-1β(IL-1β)基因的相关功能区单核苷酸多态性(SNP)与URSA疾病相关,但文献结果并不一致。本文就NOS3、IL-1β基因多态性与URSA相关性的研究进展进行综述。

血清iNOS、TREM-1、IL-1Ra表达与细菌感染性肠炎患者病情严重程度的关系及其临床意义研究

目的探究细菌感染性肠炎患者血清诱导型一氧化氮合酶(iNOS)、髓样细胞触发受体-1(TREM-1)和白细胞介素-1受体拮抗剂(IL-1Ra)表达的临床意义。方法前瞻性选取2021年2月—2023年2月广州中医药大学东莞医院收治的120例细菌感染性肠炎患者为研究对象。采集患者粪便标本,分析感染病原菌的病原学特点;根据病情严重程度将患者分为轻度组28例、中度组79例和重度组13例。另选取同期本院体检的健康体检者60例为对照组。比较各组炎症因子[血清降钙素原(PCT)、C反应蛋白(CRP)]、iNOS、TREM-1、IL-1Ra水平;采用Pearson相关分析iNOS、TREM-1、IL-1Ra与炎症因子水平的相关性;采用受试者工作特征(ROC)曲线分析血清iNOS、TREM-1、IL-1Ra对重度细菌感染性肠炎的诊断价值。结果120例细菌感染性肠炎患者共检出176株病原菌,其中氏阳性菌38株(21.59%),革兰阴性菌138株(78.41%)。4组血清PCT、CRP、iNOS、TREM-1、IL-1Ra水平比较,差异均有统计学意义(P<0.05);重度组、中度组、轻度组和对照组依次降低(P<0.05)。Pearson相关性分析结果显示,iNOS、TREM-1、IL-1Ra水平与PCT、CRP水平均呈正相关(P<0.05)。ROC曲线分析结果显示,iNOS最佳截断值为50.07 ng/L,诊断重度细菌感染性肠炎的敏感性和特异性分别为76.92%(95%CI:0.462,0.950)、81.31%(95%CI:0.726,0.882);TREM-1最佳截断值为70.11 pg/mL,诊断的敏感性和特异性分别为84.62%(95%CI:0.546,0.981)、85.05%(95%CI:0.769,0.912);IL-1Ra最佳截断值为271.75 ng/L,诊断的敏感性和特异性分别为92.31%(95%CI:0.640,0.998)、66.36%(95%CI:0.566,0.752)。结论细菌感染性肠炎患者血清iNOS、TREM-1、IL-1Ra表达升高,与患者病情严重程度存在相关性;三者在诊断重度细菌感染性肠炎方面具有良好的诊断价值,或可作为临床评估细菌感染性肠炎病情的潜在指标。