OBJECTIVETo study the effect on synthesis of nitric oxide in myocardium by local cryoablation and to investigate its mechanism.

METHODSMyocardium was cryoablated locally by a probe cooled to -60 degrees C and rewarmed by normal salt solution, nitric oxide and its synthesis enzyme were measured before and after cryoablation. L-arginine or methylene blue was added before and during cryoablation and the effect of these drugs on synthesis of nitric oxide was studied.

RESULTSNitric oxide and its synthesis enzyme decreased after cryoablation; L-arginine preserved the synthesis of nitric oxide and methylene blue inhibited the synthesis of nitric oxide. However, nitric oxide in serum did not change.

CONCLUSIONNitric oxide and its synthesis enzyme in myocardium decrease after cryoablation.

Animals ; Cryosurgery ; Myocardium ; metabolism ; pathology ; Nitric Oxide ; biosynthesis ; Nitric Oxide Synthase ; metabolism ; Rabbits

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

Long-chain acyl-coenzyme A (CoA) synthase 4 (ACSL4) is an enzyme that esterifies CoA into specific polyunsaturated fatty acids, such as arachidonic acid and adrenic acid. Based on accumulated evidence, the ACSL4-catalyzed biosynthesis of arachidonoyl-CoA contributes to the execution of ferroptosis by triggering phospholipid peroxidation. Ferroptosis is a type of programmed cell death caused by iron-dependent peroxidation of lipids; ACSL4 and glutathione peroxidase 4 positively and negatively regulate ferroptosis, respectively. In addition, ACSL4 is an essential regulator of fatty acid (FA) metabolism. ACSL4 remodels the phospholipid composition of cell membranes, regulates steroidogenesis, and balances eicosanoid biosynthesis. In addition, ACSL4-mediated metabolic reprogramming and antitumor immunity have attracted much attention in cancer biology. Because it facilitates the cross-talk between ferroptosis and FA metabolism, ACSL4 is also a research hotspot in metabolic diseases and ischemia/reperfusion injuries. In this review, we focus on the structure, biological function, and unique role of ASCL4 in various human diseases. Finally, we propose that ACSL4 might be a potential therapeutic target.
Humans ; Ferroptosis ; Apoptosis ; Phospholipids/metabolism* ; Nitric Oxide Synthase

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

Schizophrenia is one of the most serious mental disorders affecting around 1% of the world population, yet the pathophysiology of this disorder remains largely unknown. Nitric oxide (NO) has recently been discovered to be an important intracellular messenger in the glutamatergic NMDA pathway of brain and may also operate as an intercellular messenger. There is a growing interest in the role of NO in schizophrenia in that NO has been functionally linked to glutamatergic and dopaminergic systems both of which are strongly implicated in the pathophysiology of schizophrenia. Three lines of evidence have strongly implicated NO in the pathophysiology of schizophrenia. First, NO is intimately connected with glutamatergic and dopaminergic systems which are thought to be dysfunctional in schizophrenia. The second line of evidence is the finding that distribution of nitric oxide synthase (NOS) and NO metabolism are altered in schizophrenic patients. Third, NOS inhibitors may have some antipsychotic action. In conclusion, a novel direction of schizophrenia research might benefit from a more thorough understanding of the glutamate/NMDA-NO pathway. And also, compounds targeting the glutamate/NMDA-NO pathway may provide a new approach to the treatment of schizophrenia.
Brain ; Humans ; Mental Disorders ; Metabolism ; N-Methylaspartate ; Nitric Oxide Synthase ; Nitric Oxide* ; Schizophrenia*

OBJECTIVETo investigate the growth and development of nitric oxide synthase (NOS)-positive neurons in the cerebellum of human fetus in the midanaphase.

METHODThe positive expression of the NOS-positive neurons in the cerebellum of midanaphase human fetus was observed by immunohistochemistry.

RESULTSBy the sixth to seventh month of gestation, NOS-positive neurons were seen in the ependymal layer of the cerebellum. The nucleus was oval-shaped and the neurons had short and small processes. By the eighth to ninth month, NOS-positive neurons were found in the central layer of the cerebellum and the nucleus was round-, oval-, or fusiform-shaped; meanwhile, the neurons grew larger in size with richer cytoplast and heavier staining. The beaded nerve fibers reached the marginal layer and the layer became thickened on the tenth month, which generally was composed of 5 to 6 layers of NOS-positive neurons that were tightly aligned. Some NOS-positive neurons were in smaller size with the cell body and the nerve fibers grew well.

CONCLUSIONNitric oxide generated by NOS of the NOS-positive neurons in the cerebellum plays an important role in the differentiation, proliferation, and migration of neurons and gliacytes.

Cerebellar Cortex ; Fetus ; physiology ; Humans ; Immunohistochemistry ; Nerve Fibers ; Neurons ; cytology ; metabolism ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Nitric Oxide Synthase Type I

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

BACKGROUNDThe form deprivation (FD) reduces spatial contrasts and induces myopia. Nitric oxide and cyclic guanosine monophosphate (cGMP) are involved in visual signal transmission. This study investigated changes in nitric oxide synthase (NOS) activity and cGMP concentration in ocular tissues in acute and chronic form deprivation myopia.

METHODSGuinea pigs had one eye covered by translucent glass for 7, 14 or 21 days. Untreated litter mates were used as controls. NOS activity and cGMP concentrations in the retinal, choroidal and scleral tissues of FD eyes and control eyes were analyzed by radioimmunoassay after various durations of FD. The expression of NOS subtypes was identified by immunohistochemistry.

RESULTSMyopia was successfully induced in FD eyes after 14 days. Compared with control groups, the retinal NOS activity and cGMP concentrations in the FD eyes significantly increased after 14 and 21 days while the retinal NOS activity in the FD eyes was transiently suppressed by 7 days of FD. The NOS activity and cGMP concentrations of choroid and sclera in the FD eyes were higher than in the control groups at 21 days. The three isoenzymes of nitric oxide synthase were detected in the ocular tissues of guinea pigs.

CONCLUSIONSThe NOS activity and cGMP concentrations were upregulated after chronic FD and the retinal NOS activity was transiently suppressed at acute FD. The function of elevated NOS activity may be mediated by cGMP.

Animals ; Cyclic GMP ; analysis ; Guinea Pigs ; Immunohistochemistry ; Myopia ; metabolism ; Nitric Oxide ; physiology ; Nitric Oxide Synthase ; metabolism ; Refractive Errors ; Retina ; metabolism

OBJECTIVETo study the effects and mechanisms of Zuoguiyin (ZGY) on the ovarian nitric oxide (NO) production in peri-menopausal rats.

METHODSThe peri-menopausal model rats were respectively administered with low (13.78 g/kg), middle (20.67 g/kg), and high (31.00 g/kg) dose ZGY, and nilestriol for 8 weeks. Normal saline was given by gastrogavage to rats in the model group and the young control group (as the control group). The ovarian NO content and the activity of total nitric oxide synthase (NOS) were detected using nitrate reductase method and chemical colorimetry respectively. The mRNA and protein expressions of inducible NOS (iNOS), endothelial NOS (eNOS), and neuronal NOS (nNOS) were detected using RT-PCR and immunohistochemical assay.

RESULTS(1) Compared with that in the control group, the ovarian NO content and the activity of total NOS in peri-menopausal rats were significantly lower (P < 0.01). Middle and high dose ZGY could obviously up-regulate them (P < 0.01, P < 0.05). (2) The three kinds of NOS expression levels in perimenopausal rats were obviously lower when compared with those of the control group (P < 0.01). Middle dose ZGY could significantly promote all the three kinds of NOS expression levels of pre-senile rats (P < 0.01). High dose ZGY could up-regulate the expressions of iNOS and eNOS, while low dose ZGY could only enhance the iNOS expression (P < 0.01).

CONCLUSIONSThe down-regulated expressions of eNOS, iNOS, and nNOS in local ovaries resulted in decreased NOS activity and NO production, which were closely correlated with damaged microcirculatory vascular functions of ovaries in peri-menopausal rats. ZGY could protect rats' ovarian microcirculation by up-regulating the expressions of eNOS, iNOS, and nNOS, and enhancing the ovarian NOS activity and NO production.

Animals ; Drugs, Chinese Herbal ; pharmacology ; Female ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase ; metabolism ; Ovary ; drug effects ; metabolism ; Perimenopause ; Rats

In order to further investigate the mechanisms of action of berberine (Ber), we assessed the effects of Ber on the mRNA expression of nitric oxide synthases (NOS) in rat corpus cavernosum. After incubation with Ber for 1 or 3 h respectively, the levels of NOS mRNA were examined by reverse transcription polymerase chain reaction (RT-PCR). Our results showed that there were iNOS and eNOS mRNA expressions in rat corpus cavernosum. Ber enhanced eNOS mRNA expression in rat penis, but exhibited no effect on the expression of iNOS mRNA (P > 0.05). The present study indicated that the relaxation of Ber involved the NO-cGMP signal transduction pathway. The enhancing effect of Ber on eNOS mRNA expression might associated with its relaxation of corpus cavernosum.
Berberine/*pharmacology ; Connective Tissue/physiopathology ; Nitric Oxide Synthase/*biosynthesis ; Nitric Oxide Synthase/genetics ; Nitric Oxide Synthase Type I/biosynthesis ; Nitric Oxide Synthase Type I/genetics ; Nitric Oxide Synthase Type III/biosynthesis ; Nitric Oxide Synthase Type III/genetics ; Penile Erection/*physiology ; Penis/*metabolism ; Penis/physiology ; RNA, Messenger/biosynthesis ; RNA, Messenger/genetics