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Objective@#To evaluate the role of hippocampal neuronal nitric oxide synthase (nNOS)-postsynaptic dense protein 95 (PSD95) coupling in short-term memory retrieval disorder induced by sevoflurane in mice.@*Methods@#Sixteen clean-grade healthy Kunming mice of both sexes, aged 2-3 months, weighing 30-35 g, were divided into 2 groups (n=8 each) according to the random number table method: sevoflurane group (S group) and nNOS-PSD95 uncoupling agent ZL006 group (Z group). After successful establishment of dark avoidance memory, 3.3% sevoflurane and 40% O2 were inhaled for 2 h in both groups, and normal saline 1.5 ml was intraperitoneally injected in group S and ZL006 1 mg/kg in group Z at 30 min before anesthesia.The step-through latency and error times were recorded before anesthesia and at 12 h after the end of anesthesia.The mice were then sacrificed, and hippocampal tissues were taken for determination of the expression of nNOS and PSD95 (by Western blot) and co-expression of nNOS and PSD95 (by immunoprecipitation).@*Results@#Compared with that before anesthesia, the step-through latency was significantly shortened, and the error times were increased at 12 h after anesthesia in group S (P<0.05), and no significant change was found in the above indicators in group Z (P>0.05). Compared with group S, the step-through latency was significantly prolonged, error times were decreased, the co-expression of nNOS and PSD95 was down-regulated (P<0.05), and no significant change was found in the expression of nNOS and PSD95 in group Z (P>0.05).@*Conclusion@#The mechanism by which sevoflurane induces short-term memory retrieval disorder may be related to promoting the coupling of nNOS to PSD95 in the hippocampus of mice.
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Objective To evaluate the role of hippocampal neuronal nitric oxide synthase(nNOS)-postsynaptic dense protein 95(PSD95)coupling in short-term memory retrieval disorder induced by sevoflu-rane in mice.Methods Sixteen clean-grade healthy Kunming mice of both sexes,aged 2-3 months,weighing 30-35 g,were divided into 2 groups(n＝8 each)according to the random number table method:sevoflurane group(S group)and nNOS-PSD95 uncoupling agent ZL006 group(Z group).After successful establishment of dark avoidance memory,3.3％sevoflurane and 40％O2 were inhaled for 2 h in both groups,and normal saline 1.5 ml was intraperitoneally injected in group S and ZL006 1 mg/kg in group Z at 30 min before anesthesia.The step-through latency and error times were recorded before anesthesia and at 12 h after the end of anesthesia.The mice were then sacrificed,and hippocampal tissues were taken for de-termination of the expression of nNOS and PSD95(by Western blot)and co-expression of nNOS and PSD95(by immunoprecipitation).Results Compared with that before anesthesia,the step-through latency was significantly shortened,and the error times were increased at 12 h after anesthesia in group S(P＜0.05),and no significant change was found in the above indicators in group Z(P>0.05).Compared with group S,the step-through latency was significantly prolonged,error times were decreased,the co-expression of nNOS and PSD95 was down-regulated(P＜0.05),and no significant change was found in the expression of nNOS and PSD95 in group Z(P>0.05).Conclusion The mechanism by which sevoflurane induces short-term memory retrieval disorder may be related to promoting the coupling of nNOS to PSD95 in the hippocam-pus of mice.
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Objective@#To investigate the effects of estrogen and remifemin on the expression of neuronal nitric oxide synthase (nNOS), transient receptor potential vanilloid 1 (TRPV1), muscarinic acetylcholine receptor, member 1 and 3 (M1 and M3 receptor) and acetylcholinesterase (AChE) in the submandibular gland of rats.@*Methods@#Forty SD female adult rats were divided into SHAM group (sham operation), OVX group (ovarian removal), OVX+E group (ovarian removal + estrogen treatment) and OVX+ICR group (ovarian removal + remifemin treatment), 10 per group. The rats were recovered for 2 weeks after operation. The SHAM group and the OVX group were treated with distilled water, the OVX+E group and the OVX+ICR group were treated with β-estradiol and remifemin respectively. After 4 weeks, the location and expression of nNOS, TRPV1, M1 and M3 receptors in the submandibular gland were evaluated by immunohistochemistry. The changes of AChE expression in rat submandibular gland were observed by AChE staining.@*Results@#Compared with SHAM group (0.23±0.02, 0.28±0.01, 0.25±0.03, 0.19±0.03), the expression of nNOS, TRPV1, M1 and M3 receptors in OVX group (0.16±0.01, 0.21±0.01, 0.15±0.02, 0.09±0.02) were significantly lower (P<0.05); there were no significant difference between OVX+E group (0.23±0.01, 0.28±0.02, 0.23±0.03, 0.19±0.01) and SHAM group (P>0.05). But compared with OVX group, the expression of nNOS, TRPV1 and M3 receptors in OVX+ICR group were no significantly changed (P>0.05), and only M1 receptor expression (0.22±0.03) was significantly increased (P<0.05). The expression of AChE in OVX group (0.14±0.01) was significantly higher than that in SHAM group (0.10±0.01) (P<0.05). The expression of AChE in OVX+E group (0.15±0.01) was significantly higher than that in SHAM group (P<0.05). The expression of AChE in OVX+ICR group (0.09±0.01) was not significantly different from that in SHAM group (P>0.05).@*Conclusions@#Estrogen can significantly increase the expression of nNOS and TRPV1 in the submandibular gland of rats, suggesting that estrogen may regulate the salivary secretion function of the submandibular gland through nNOS and TRPV1. The mechanism of remifemin is different from that of estrogen, and remifemin does not play a regulatory role by nNOS and TRPV1.
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Nitric oxide synthase (NOS) is a key enzyme for production of nitric oxide (NO) in vivo.With the deepening of study on biochemical and molecular characteristics of NOS,the intervention of NOS-NO pathway playing an important role in gastrointestinal motility disorder is appreciated.This article reviewed the progress of research on relationship between neuronal nitric oxide synthase (nNOS) and gastrointestinal motility disorders.
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Objective To evaluate the effects of dexmedetomidine on the expression of neuronal nitric oxide synthase (nNOS) and c-fos in the lcuos cruleus (LC) in a rat model of endotoxic shock.Methods Twentyeight male Sprague-Dawley rats,aged 8 weeks,weighing 250-300 g,were randomly divided into 4 groups (n =7 each):control group (group C),endotoxic shock induced by lipopolysaccharide (LPS) group (group L),lowdose dexmedetomidine group (groupLD) and high-dose dexmedetomidine group (group HD).Normal saline 0.5 ml/kg was injected via the tail vein in C and L groups.Dexmedetomidine 0.5 and 4.5μg/kg were injected via the tail vein in group LD and group HD,respectively.Normal saline 0.5 ml/kg was injected via the tail vein 10 min later in C,while LPS 5 mg/kg was injected intravenously 10 min later in the other groups.The rats were sacrificed and their brains were removed for determination of brain water content,the number of nNOS and c-fos positive cells and expression of nNOS and c-fos in the LC by immuno-histochemistry.Results Compared with group C,the brain water content was significantly increased,the number of nNOS and c-fos positive cells in the LC was enlarged,and the expression of nNOS and c-fos in the LC was up-regulated in group L (P ＜ 0.05).The brain water content was significantly lower,the number of nNOS and c-fos positive cells in the LC was smaller,and the expression of nNOS and c-fos in the LC was lower in LD and HD groups than in group L (P ＜ 0.05).The number of nNOS and c-fos positive cells in the LC was significantly smaller,and the expression of nNOS and c-fos in the LC was lower in HD group than in group LD (P ＜ 0.05).Conclusion Dexmedetomidine can down-regulate the expression of nNOS and c-fos in the LC,which may be one of brain-protective mechanisms of dexmedetomidine in a rat model of endotoxic shock.
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Objective To investigate the effects of ketamine on neuronal nitric oxide synthase (nNOS) activity and carboxy-terminal PDZ ligand of nNOS (CAPON) expression in the prefrontal lobe of mentally depressed rats.Methods Adult male Sprague-Dawley rats,aged 2.5-3.0 months,weighing 210-260 g,were used in the study.Menial depression was induced by exposing the rats to chronic unpredictable mild stress.Twenty-four animals in which mental depression was successfully induced were randomly divided into 2 groups (n =12 each):mental depression group (group D) and ketamine group (group K).Another 12 rats were chosen and served as control group (group C).Group K received intraperitoneal ketamine 10 mg/kg once a day for 7 consecutive days,while groups C and D received intraperitoneal normal saline 10 ml/kg instead of ketamine.Sucrose preference test and open field test were performed before administration and at 1 day after the end of administration.The total distance,number of rearing and sucrose preference percentage (SPP) were recorded.The rats were sacrificed 1 day after the last test for determination of the expression of nNOS and CAPON protein (using immuno-histochemistry)and mRNA (by RT-PCR) in the prefrontal lobe.Results Compared with group C,the total distance was shortened,the number of rearing and SPP were significantly decreased,the expression of nNOS protein and mRNA was up-regulated and the expression of CAPON protein and mRNA was down-regulated in groups D and K (P ＜ 0.05).Compared with group D,the total distance was prolonged,the number of rearing and SPP were significantly increased,the expression of nNOS and mRNA was down-regulated and the expression of CAPON protein and mRNA was up-regulated in group K (P ＜ 0.05).Conclusion Ketamine can improve the depressive state through promoting the expression of CAPON and inhibiting nNOS activity in the prefrontal lobe of mentally depressed rats.
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Objective To explore the expression of nitric oxide synthases including neuronal nitric oxide synthases(nNOS), inducible nitric oxide synthases(iNOS), endothelial nitric oxide synthases (eNOS) in neurogenic bladder tissues, and analyze it's producing feature and significance. Methods There were 30 cases with neurogenic bladder(18 males, 12 females). The average age was 6.3±3.1 years. All patients appeared with myelodysplasia, urinary and fecal incontinence in different degree. Twenty-six cases were manifested with hyperreflexia bladders, and all patients were treated with surgical procedures. During operation, collected bladder tissue samples including tissues of apex vesicae and tissues of bladder neck, and all tissues were enveloped with mineral wax. All tissues were detected for nNOS, iNOS, and eNOS respectively in tissues of apex vesicae and tissues of bladder neck,and with normal bladder tissues as control group (bladder tissues of hypospadia, 10 cases), and according to clinical features, to explore the expression of NOS, and to analyze the relationship among them. Results In normal apex vesicae tissues, all cases stained with nNOS, and distributed among bundles of smooth muscles, and surface of smooth muscles and interstitial tissue, histochemica;score (HS) 2.8-4.0 and 1.2-2.7. There were no stained cells in bladder tissues of iNOS, and HS was very low, HS:0-0. 4 and 0-0.1 ;eNOS mainly distributed in interstitial tissues in rarefaction manners, and mainly in vascular endothelial cell (VEC), and smooth muscles had no stainings the most expression among them was nNOS, and mainly distributed in bladder neck tissues. In neurogenic bladder tissues, the main expression of NOS type was iNOS, and nNOS decreased significantly. eNOS mainly expressed in VEC among interstitial tissues, and had no staining in smooth muscle cells and collagenoblast and rarefaction of microvessel in bladder tissues, and microvessel density decreased significantly than normal bladder tissues. Microvessal density(MVD) in bladder tisssus (6. 8± 3.2/100per square) was less than that in normal tissues (16.7±6.3/100 per square). Conclusions In normal bladder tissues, nNOS mainly distributes in bladder neck and urethra, and nitric oxide mainly derives from nNOS. Much more matrix fibers, fewer nitrogenergic nerves, and less nNOS expression are seen in neurogenic bladder interstitial tissue. There are more iNOS expressions in bladder tissues,and NO is mainly derived from iNOS, and it may play an important role in pathological bladder tissues, especially in fibrosis of bladder wall. eNOS may be considered as angiopoietic labeling, and may evaluate the blood supply of bladder.