OBJECTIVETo explore the possible mechanism of the erector spinal muscles in idiopathic scoliosis by comparing the expression and localization of neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS) of the thoracic erector spinal muscles on convex side and concave side.

METHODSThe patient group comprised 8 females and 2 males who were scheduled for spinal surgery. The apex of scoliotic curve in these patients arose between T6 and T11. The mean age was 14.3 (range 12-17) years, and the mean Cobb angle was 57.7 degrees (range 45 degrees-85 degrees). Muscle biopsies were taken bilaterally during surgery from the superficial multifidus muscle at the apex of the curve between the 6th and 11th thoracic vertebral levels. Part of the tissue was fixed in formalin and stained with hematoxylin and eosin; the remaining tissue was snap frozen and processed for immunohistochemistry and Western blot. Immunocytochemistry for nNOS and iNOS were performed using the EnVision two-step method. Western blot was done with antibodys to nNOS and iNOS. Immunoreactive bands were visualized by enhanced chemiluminescence according to the manufacturer's specifications (Amersham Corp).

RESULTSnNOS protein in the erector spinal muscles was localized at the sarcolemma. Western blot demonstrated that nNOS protein expression in the concave side of erector spinal muscles is more than that in the convex side. A significant decrease in nNOS protein and activity was found on the convex side of erector spinal muscles from idiopathic scoliosis patients; There was a little immunoreactivity to iNOS in erector spinal muscles. There was little difference in iNOS protein expression between both sides of the curve. Western blot detected the same results.

CONCLUSIONThere is a greater expression of nNOS and iNOS on the concave side than on the convex side, suggesting nNOS and iNOS may play a role in the pathogenesis of idiopathic scoliosis.

Adolescent ; Child ; Female ; Humans ; Immunohistochemistry ; Male ; Muscle, Skeletal ; cytology ; enzymology ; Nitric Oxide Synthase ; analysis ; metabolism ; Nitric Oxide Synthase Type I ; Nitric Oxide Synthase Type II ; Scoliosis ; enzymology

The expression of nitric oxide synthase (NOS) isoforms in the ovaries of pigs was examined to study the involvement of nitric oxide, a product of NOS activity, in the function of the ovary. Western blot analysis detected three types of NOS in the ovary, including constitutive neuronal NOS (nNOS), endothelial NOS (eNOS) and inducible NOS (iNOS); eNOS immunoreactivity was more intense compared with that of iNOS or nNOS. Immunohistochemical studies demonstrated the presence of nNOS and eNOS in the surface epithelium, stroma, oocytes, thecal cells, and endothelial cells of blood vessels. Positive immunoreactions for nNOS and iNOS were detected in the granulosa cells from multilaminar and antral follicles, but not in those of unilaminar follicles. iNOS was detected in the surface epithelium, oocytes, and theca of multilaminar and antral follicles. Taking all of the findings into consideration, the observed differential expression of the three NOS isoforms in the ovary suggests a role for nitric oxide in modulating reproduction in pigs.
Animals ; Blotting, Western/veterinary ; Female ; Immunohistochemistry/veterinary ; Nerve Tissue Proteins/*biosynthesis ; Nitric Oxide/metabolism ; Nitric Oxide Synthase/*biosynthesis ; Nitric Oxide Synthase Type I ; Nitric Oxide Synthase Type II ; Nitric Oxide Synthase Type III ; Ovarian Follicle/*enzymology/growth&development ; Swine/*physiology

OBJECTIVETo study the effects of insulin-like growth factor II (IGF-II) on regulating the levels of nitric oxide (NO) and the mRNA transcriptions of inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) in mouse osteoblast-like cells.

METHODSMouse osteoblastic cell line MC3T3-E1 was selected as the effective cell of IGF-II. After the cells were treated with IGF-II at different concentrations for different intervals of time, MTT colorimetry was used for examining the cell proliferation. Nitrate reductase method was applied for detecting the NO concentrations in cell culture supernatants and RT-PCR employed for determining the levels of cellular iNOS and eNOS mRNAs.

RESULTSAfter the MC3T3-E1 cells were treated with IGF-II at the dosages of 1 microg/L for 72 h, 10 and 100 microg/L for 24, 48 and 72 h respectively, all the MTT values increased markedly (P < 0.05 or P < 0.01). After the cells were treated for 48 and 72 h at the dosage of 100 microg/L IGF-II respectively, the levels of NO in the supernatants of cell cultures and cellular iNOS mRNA decreased significantly (P < 0.01). However, the levels of eNOS mRNA in the cells treated with any of the IGF-II dosages for the different times were stable (P > 0.05).

CONCLUSIONSIGF-II at the dosages of 1 approximately 100 microg/L showed the effects on promoting proliferation, which as probably due to the maintenance of low NO levels. Inducible NOS gene expression at the level of transcription was down regulated in the MC3T3-E1 cell treated with higher dosage of IGF-II (100 microg/L) but eNOS mRNA was not, which might be one of the mechanisms for the maintenance of low NO levels.

3T3 Cells ; Animals ; Insulin-Like Growth Factor II ; pharmacology ; Mice ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; biosynthesis ; genetics ; Nitric Oxide Synthase Type II ; Nitric Oxide Synthase Type III ; Osteoblasts ; cytology ; drug effects ; enzymology ; RNA, Messenger ; biosynthesis

In practice of forensic medicine, potential disease can be associated with fatal asphyxia in restraint position. Research has demonstrated that nitric oxide (NO) and nitric oxide synthase (NOS) are plentifully distributed in skeletal muscle, contributing to the regulation of contractile and relaxation. In the current study, respiratory functions, indices of diaphragmatic biomechanical functions ex vivo, as well as NO levels in serum, the expressions of diaphragmatic inducible NOS (iNOS) mRNA, and the effects of L-NNA on contractility of the diaphragm were observed in sepsis induced by cecal ligation and puncture (CLP) under the condition of restraint position. The results showed that in the CLP12-18h rats, respiratory dysfunctions; indices of diaphragmatic biomechanical functions (Pt, +dT/dt(max), -dT/dt(max), CT, Po, force over the full range of the force-frequency relationship and fatigue resistance) declined progressively; the NO level in serum, and iNOS mRNA expression in the diaphragm increased progressively; force increased significantly at all stimulation frequencies after L-NNA pre-incubation. Restraint position 1 h in CLP12 h rats resulted in severe respiratory dysfunctions after relative stable respiratory functions, almost all the indices of diaphragmatic biomechanical functions declined further, whereas little change took place in NO level in serum and diaphragmatic iNOS mRNA expression; and the effects of L-NNA were lack of statistical significance compared with those of CLP12 h, but differed from CLP18 h group. These results suggest that restraint position and sepsis act together in a synergistic manner to aggravate the great reduction of diaphragmatic contractility via, at least in part, the negative modulation of NO, which may contribute to the pathogenesis of positional asphyxia.
Animals ; Asphyxia ; Diaphragm/physiology* ; Muscle Contraction ; Muscle, Skeletal ; Nitric Oxide/metabolism* ; Nitric Oxide Synthase ; Nitric Oxide Synthase Type II ; Rats ; Respiration Disorders ; Restraint, Physical ; Sepsis

OBJECTIVETo study the changes in the microglial cells and the activity of nitric oxide synthase (NOS), inducible nitric oxide synthase (iNOS) and constitutive nitric oxide synthase (cNOS) in the striatum of rats with methamphetamine (METH) treatment.

METHODSThe rats were randomly divided into two groups for injections with METH or saline. Specific antibody against OX-42 was used to detect the changes in the morphology and the number of microglia, and the activities of NOS, iNOS and cNOS were compared between the two groups.

RESULTSThe microglial cells were activated and their number significantly increased in the striatum of rats with METH treatment as compared with those in the saline group. The activated microglial cells showed bushy and amoeboid morphologies in the METH group. METH also significantly enhanced the activities of NOS, iNOS and cNOS in the striatum (P < 0.05).

CONCLUSIONMicroglial activation and increased NOS activity may participate in METH-induced neurotoxicity in rat striatum.

Animals ; Corpus Striatum ; enzymology ; Male ; Methamphetamine ; pharmacology ; Microglia ; metabolism ; Nitric Oxide Synthase ; metabolism ; Nitric Oxide Synthase Type II ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Random Allocation ; Rats ; Rats, Wistar

BACKGROUNDExposure of adult mice to more than 95% O(2) produces a lethal injury by 72 hours. Nitric oxide synthase (NOS) is thought to contribute to the pathophysiology of murine hyperoxia-induced acute lung injury (ALI). Osteopontin (OPN) is a phosphorylated glycoprotein produced principally by macrophages. OPN inhibits inducible nitric oxide synthase (iNOS), which generates large amounts of nitric oxide production. However, the relationship between nitric oxide and endogenous OPN in lung tissue during hyperoxia-induced ALI has not yet been elucidated, thus we examined the role that OPN plays in the hyperoxia-induced lung injury and its relationships with NOS.

METHODSOne hundred and forty-four osteopontin knock-out (KO) mice and their matched wild type background control (WT) were exposed in sealed cages > 95% oxygen or room air for 24- 72 hours, and the severity of lung injury was assessed; expression of OPN, endothelial nitric oxide synthase (eNOS) and iNOS mRNA in lung tissues at 24, 48 and 72 hours of hyperoxia were studied by reverse transcription-polymerase chain reaction (RT-PCR); immunohistochemistry (IHC) was performed for the detection of iNOS, eNOS, and OPN protein in lung tissues.

RESULTSOPN KO mice developed more severe acute lung injury at 72 hours of hyperoxia. The wet/dry weight ratio increased to 6.85 +/- 0.66 in the KO mice at 72 hours of hyperoxia as compared to 5.31 +/- 0.92 in the WT group (P < 0.05). iNOS mRNA (48 hours: 1.04 +/- 0.08 vs. 0.63 +/- 0.09, P < 0.01; 72 hours: 0.89 +/- 0.08 vs. 0.72 +/- 0.09, P < 0.05) and eNOS mRNA (48 hours: 0.62 +/- 0.08 vs. 0.43 +/- 0.09, P < 0.05; 72 hours: 0.67 +/- 0.08 vs. 0.45 +/- 0.09, P < 0.05) expression was more significantly increased in OPN KO mice than their matched WT mice when exposed to hyperoxia. IHC study showed higher expression of iNOS (20.54 +/- 3.18 vs. 12.52 +/- 2.46, P < 0.05) and eNOS (19.83 +/- 5.64 vs. 9.45 +/- 3.82, P < 0.05) in lung tissues of OPN KO mice at 72 hours of hyperoxia.

CONCLUSIONOPN can protect against hyperoxia-induced lung injury by inhibiting NOS.

Animals ; Hyperoxia ; genetics ; physiopathology ; Immunohistochemistry ; Lung ; metabolism ; Lung Injury ; etiology ; genetics ; metabolism ; Mice ; Mice, Knockout ; Nitric Oxide Synthase ; genetics ; metabolism ; Nitric Oxide Synthase Type II ; genetics ; Nitric Oxide Synthase Type III ; genetics ; Osteopontin ; genetics ; physiology ; Reverse Transcriptase Polymerase Chain Reaction

AIMTo investigate the effects of simulated microgravity on dilatory responsiveness and NOS expression of abdominal aorta in rats.

METHODSTwenty male healthy SD rats, which body weight ranged from 300 g to 330 g, were divided into control group and simulated microgravity group randomly. After 4 weeks, using isolated arterial rings from rats, arterial dilatory responsiveness of abdominal aorta were examined in vitro. And the expression of nitric oxide synthase (NOS), including endothelial NOS (eNOS) and inducible NOS (iNOS), were observed by Western blot.

RESULTSDilatory responses of arterial rings to L-Arginine (10(-8)-10(-3) mol/L), and Acetylcholine mol/L) were decreased in simulated microgravity rats compared with that of controls; but dilatory responses of isolated aortic rings to sodium nitroprusside (mol/L) and 8-bromo-cGMP(mol/L) were similar in both simulated microgravity rats and control rats. The expression of both eNOS and iNOS had not showed significant differences between two groups.

CONCLUSIONThe data indicate that endothelium dependent vasorelaxation in abdominal aortic rings are decreased by 4-week simulated microgravity, and this change may be result from altered NOS activity in endothelium.

Animals ; Aorta, Abdominal ; metabolism ; Arginine ; metabolism ; Cyclic GMP ; metabolism ; Male ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type II ; metabolism ; Nitric Oxide Synthase Type III ; metabolism ; Rats ; Rats, Sprague-Dawley ; Weightlessness Simulation

To investigate the effects of ischemia-reperfusion on the levels of nitric oxide and nitric oxide synthase isoforms (nNOS and iNOS), rat organotypic hippocampus slice were cultured in vitro and subjected to ischemia by oxygen-glucose deprivation (OGD) for 30 min and then placed in the normal culture condition. The ischemia-reperfusion produced a time-dependent increase in nitrite levels in the culture medium. Reverse transcriptional-polymerase chain reaction showed augmented levels of mRNA for both nNOS and iNOS when compared with control at 12 h and remained increase at 36 h after OGD (P < 0.05). The protein levels of both nitric oxide synthase isoforms increased significantly as determined by Western Blot. OGD also caused neurotoxicity in this model as revealed by the elevated lactate dehydrogenase (LDH) efflux into the incubation solution. The results suggest that organotypic hippocampus slice is a useful model in studying ischemia-reperfusion brain injury. NO and NOS may play a critical role in the ischemia-reperfusion brain damage in vitro.
Animals, Newborn ; Cell Hypoxia ; Hippocampus/cytology ; Hippocampus/*metabolism ; Nitric Oxide/*metabolism ; Nitric Oxide Synthase Type I/*metabolism ; Nitric Oxide Synthase Type II/*metabolism ; RNA, Messenger/metabolism ; Rats, Sprague-Dawley ; Reperfusion Injury/*metabolism ; Tissue Culture Techniques

OBJECTIVETo study the effect of electroacupuncture on nitric oxide synthase (NOS) in rats with cerebral ischemia-reperfusion injury.

METHODSFocal cerebral ischemia-reperfusion model was established using modified intravascular suture technique. The NO content in the brain tissue was detected by nitrite reduction and the expressions of nNOS and iNOS were detected by immunohistochemistry. Eighty rats in this experiment were divided into the normal group, the cerebral ischemia-reperfusion injury model group (as the model group), the cerebral ischemia-reperfusion injury + electroacupuncture group (as the acupuncture group), and the cerebral ischemia-reperfusion injury + phosphatidylinositol 3 kinase (PI3-K) inhibitor group (as the inhibitor group). Each group consisted of twenty rats. Five microL PI3-K inhibitor LY294002 (400 microL) was slowly injected at the lateral cerebral ventricle of rats in the inhibitor group at a constant speed using microinjector according to Konig Klippel atlas of the stereotaxis instrument. Shuigou (DU26) and Chengjiang (RN24) were selected to determine levels of NO and NOS.

RESULTSAfter 24-h ischemia-reperfusion, the NO levels of the hippocampus and the cerebral cortex increased abnormally, and the expressions of nNOS and iNOS increased, showing significant difference when compared with those of the normal group (P<0.05). By electroacupuncture at Shuigou (DU26) and Chengjiang (RN24), the ischemic cerebral ischemia-reperfusion injury neuron loss was inhibited. Meanwhile, the high levels of NO, nNOS and iNOS in the cerebral cortex and the hippocampus were significantly inhibited (P<0.05). The abnormally increased expressions of nNOS and iNOS were reversed, showing significant difference when compared with the model group (P<0.05). But when compared with the normal group, there was no significant difference (P>0.05). The effects of electroacupuncture reversed the abnormally increased NO levels of the hippocampus and the cerebral cortex and expressions of nNOS and iNOS after LY294002 oppressed anti-PI3K to block the TrkA acceptor circuit. The NO levels of the hippocampus and the cerebral cortex and expressions of nNOS and iNOS increased again, showing significant difference when compared with the acupuncture group (P<0.05).

CONCLUSIONSAcupuncture fought against cerebral ischemia and reperfusion in the loss of neurons, at the same time, the abnormal regulation of NOS had reverse effect partly through TrkA/PI3K mediated signal transduction pathway.

Animals ; Brain Ischemia ; metabolism ; Electroacupuncture ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type I ; metabolism ; Nitric Oxide Synthase Type II ; metabolism ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; metabolism ; Signal Transduction

Increasing lines of evidence has been accumulated that nitric oxide (NO) and nitric oxide synthase (NOS) distribute plentifully in the rostral ventrolateral medulla (RVLM) and contribute to cardiovascular regulation. In the present study, the expressions of neuronal and inducible isoform of NOS (nNOS and iNOS) were observed in the RVLM of acute myocardial ischemia (AMI) Wistar rats experienced electroacupuncture (EA) treatment, thereby the cardiovascular effects of NO in the RVLM were investigated and the mechanism of acupuncture effect on AMI was inferred. The results indicated that in the AMI rats, cardiac functions were markedly attenuated with high serum level of brain natriuretic peptide (BNP) and norepinephine (NE), the number of nNOS-immunoreactive cells and nNOS mRNA exprossion in the RVLM area were increased, while those of iNOS were lowered. EA at "Neiguan" acupoints (Pe 6) 30 min daily for successive 5 d resulted in an improvement of the cardiac functions, decreases in NE and BNP levels; it also increased the expression of iNOS and decreased the expression of nNOS in the RVLM. These results suggest that the curative effect of acupuncture on AMI is possibly attributable to the differential regulation of NOS/NO in the RVLM, leading to decreased sympathetic outflow and improvement of cardiac functions.
Acupuncture Therapy ; Animals ; Electroacupuncture ; Medulla Oblongata ; metabolism ; Myocardial Ischemia ; metabolism ; therapy ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type I ; metabolism ; Nitric Oxide Synthase Type II ; metabolism ; Rats ; Rats, Wistar