中缝背核注射L-NAME抑制炎性痛大鼠脊髓Fos的表达

目的 观察中缝背核(DRN)内一氧化氮合酶(NOS)对炎性痛大鼠脊髓伤害性信息传递的调控作用.方法 建立大鼠单侧足底甲醛炎性痛模型,采用行为学、c-Fos免疫组织化学及烟酰胺腺嘌呤二核苷酸磷酸黄递酶(NADPH-d)组织化学技术,观察甲醛诱发炎性痛后大鼠DRN内NADPH-d、NADPH-d/Fos双标阳性神经元数量的变化;同时观察DRN内预先给予NOS抑制剂L-NAME对甲醛致痛大鼠疼痛评分及脊髓Fos蛋白表达的影响.结果 单侧足底注射甲醛后,DRN内NADPH-d、NADPH-d/Fos双标阳性神经元的数量增加.DRN内预先注射L-NAME降低炎性痛大鼠的疼痛学评分及脊髓Fos阳性神经元的数量.结论 DRN内NOS可能促进甲醛炎性痛大鼠脊髓伤害性信息的传递.     

吗啡戒断时M2毒蕈碱受体介导大鼠蓝斑核中nNOS表达增强

目的:观察脊髓不同M受体亚型对纳络酮催促吗啡戒断大鼠戒断症状评分以及蓝斑核nNOS表达变化的影响.方法:采用nNOS免疫组织化学、鞘内注射和反义寡核苷酸技术.结果:鞘内注射M_2-AS可显著减少吗啡戒断症状评分,M_1-AS虽可部分减轻戒断症状,但总的作用弱于 M_2-AS;吗啡依赖大鼠蓝斑核nNOS表达增加,用纳络酮催促戒断后nNOS表达进一步增加,鞘内注射M_2-AS可抑制在吗啡戒断时蓝斑核nNOS的表达增强,而M_1-AS对其无影响.结论:脊髓M_2受体介导吗啡戒断大鼠蓝斑核nNOS的表达增加.     

鞘内注射右美托咪啶对吗啡戒断大鼠脊髓nNOS表达的影响

目的 观察鞘内注射右美托咪啶对吗啡依赖大鼠纳洛酮催促戒断反应和脊髓神经元型一氧化氮合酶(nNOS)表达的影响.方法 建立大鼠吗啡依赖和戒断模型,分为正常对照(C)组、吗啡依赖(MD)组、吗啡戒断(MW)组和右美托咪啶(DEX)组,采用行为学(n=8)、免疫组织化学(n=6)和Western blot法(n=4)观察鞘内注射右美托咪啶对吗啡依赖大鼠纳洛酮催促戒断反应和脊髓nNOS表达的影响.结果 鞘内注射右美托咪啶可减轻吗啡依赖大鼠戒断症状:MW组戒断症状评分为(28.6±4.9)分,高于DEX组的(17.8±3.8)分(P＜0.05);MW组促诱发痛(TEA)评分为(13.5±2.6)分,高于DEX组的(8.6±2.5)分(P＜0.05).鞘内注射右美托咪啶可减少脊髓背角nNOS阳性神经元的数目:DEX组为(180±31)个,低于MW组的(238±40)个(P＜0.05);DEX组脊髓nNOS蛋白表达也减少.结论 右美托咪啶能抑制吗啡戒断大鼠脊髓nNOS表达.     

预先应用咪哒唑仑抑制小鼠和大鼠吗啡戒断反应

目的:研究咪哒唑仑对小鼠和大鼠吗啡戒断反应的影响.方法:实验中采用急性和慢性吗啡依赖和纳洛酮催促戒断模型.使用放免法测定cAMP含量,免疫组织化学方法观察Fos蛋白表达变化.结果:合用咪哒唑仑和吗啡可抑制小鼠急性和慢性吗啡依赖的发展.在急性吗啡依赖小鼠,咪哒唑仑-吗啡组纳络酮催促跳跃的ED_(50)(10.4,8.5-12.3 mg/kg)明显大于生理盐水-吗啡组(3.0,1.9-4.3 mg/kg)(P<0.01).在慢性吗啡依赖小鼠,咪哒唑仑-吗啡组纳络酮催促跳跃的发生率和跳跃次数明显低于生理盐水-吗啡组(P<0.01).预先使用咪哒唑仑抑制吗啡戒断大鼠脊髓Fos蛋白表达,但不能抑制脊髓cAMP含量的增加.结论:咪哒唑仑通过抑制脊髓神经元敏感化减轻吗啡戒断反应,cAMP信号转导通路不参与介导这一效应.     

神经元型一氧化氮合酶反义寡脱氧核苷酸抑制大鼠吗啡戒断症状

目的　观察鞘内或侧脑室注射神经元型一氧化氮合酶 (nNOS)反义寡脱氧核苷酸对大鼠吗啡戒断症状的影响。方法　根据基因结构设计nNOS或eNOS反义寡脱氧核苷酸片段 ,用逆转录聚合酶链反应 (RT PCR)测定nNOSmR NA表达。结果　吗啡依赖大鼠在纳洛酮激发前 2 4h鞘内注射nNOS反义寡脱氧核苷酸抑制所有大鼠吗啡戒断症状如湿狗摇动、扭体及激惹、腹泻、体重减少、咬牙和流涎。eNOS反义寡脱氧核苷酸对吗啡戒断症状总评分值没有影响 ,但减少腹泻、体重减轻值和咬牙等评分值。侧脑室注射nNOS反义寡脱氧核苷酸减少吗啡戒断症状 ,eNOS反义寡脱氧核苷酸对吗啡戒断症状没有影响。鞘内注射nNOS反义寡脱氧核苷酸后脊髓nNOSmRNA的相对表达几乎消失 ,iNOS的表达增加 ;而eNOS反义寡脱氧核苷酸处理后对nNOS和iNOS的表达没有影响。结论　nNOS基因表达介导了吗啡戒断反应过程 ,抑制nNOS基因表达可增加脊髓i NOS基因的表达。     

鞘内注射促皮质素抑制甲醛痛敏大鼠脊髓NOS阳性神经元增多

目的:研究鞘内注射促皮质素(Cor)对甲醛痛敏大鼠脊髓背角一氧化氮合酶(NOS)阳性神经元增多的影响。方法:采用痛级均数(PIR)测定、NADPH-d组织化学法、Fos免疫组织化学法染色,观察鞘内注射(ith)Cor对甲醛痛敏大鼠脊髓背角NOS阳性神经元、Fos免疫反应神经元、NOS/Fos双标记神经元及痛敏的影响。结果:ith Cor(0.5-1.5U)均能显著抑制甲醛引起的大鼠脊髓背角NOS、Fos、NOS/Fos阳性神经元的增多和痛敏反应,其作用为ith NOS底物左旋精氨酸(Arg,5-15nmol)部分翻转。结论:Cor通过抑制大鼠脊髓背角NOS阳性神经元的增多抑制痛敏。     

一氧化氮合酶抑制剂抑制吗啡依赖及戒断大鼠脊髓神经元ERK的表达

目的探讨鞘内分别注射非选择性一氧化氮合酶(NOS)抑制剂L-NAME、选择性神经元型一氧化氮合酶(nNOS)抑制剂7-硝基吲哚(7-NI)对吗啡戒断大鼠戒断症状和痛敏行为以及脊髓神经元p-ERK表达的影响。方法采用吗啡依赖及戒断模型,分为正常对照组、依赖组、戒断组、L-NAME组(L-NAME)、7-NI组(7-NI),分别作行为学评分(n=8)、免疫组织化学(n=6)和免疫印迹检测(n=4)。结果实验结果表明,①鞘内注射L-NAME、7-NI可明显减轻吗啡依赖大鼠戒断症状,戒断组戒断症状评分为28.6±4.89,L-NAME组、7-NI组分别为22.1±4.52(P<0.05)、16.2±3.99(P<0.01);戒断组促诱发痛评分(touch evoked agitationscores,TEA score)为13.5±2.55,L-NAME组、7-NI组分别为9.8±3.11(P<0.05)、7.5±2.56(P<0.01)。②鞘内注射L-NAME、7-NI可明显减少胸腰段脊髓背角Fos阳性神经元的数目,L-NAME组、7-NI组分别为293±47、267±52,均低于戒断组(380±71,P<0.05,P<0.01)。③L-NAME、7-NI组p-ERK阳性神经元的数目分别为46.8±11.58、40.5±8.55,均低于戒断组(66.6±11.6,P<0.05,P<0.01),两给药组脊髓p-ERK蛋白的表达也减少。④W estern b lot显示:鞘内注射NOS明显抑制吗啡戒断大鼠脊髓p-ERK蛋白表达增加。结论脊髓水平NO参与吗啡依赖和戒断反应,ERK信号通路可能介导NO的上述作用。     

三七总皂甙对吗啡戒断大鼠大脑皮质M乙酰胆碱受体mRNA及蛋白表达的影响

目的:研究三七总皂甙(PNS)对吗啡戒断大鼠大脑皮质m2,m5乙酰胆碱受体(AChR)mRNA及蛋白表达的影响,探讨PNS抑制吗啡戒断症状的作用机制。方法:以剂量递增法建立大鼠吗啡依赖模型(MOR组),以腹腔注射(ip)纳洛酮建立催促戒断模型(NAL组),大鼠在给予吗啡的同时,采用3种不同剂量PNS(100、200、400mg.kg-1)灌胃(ig)。采用RT-PCR和Western-blot方法分别观察PNS对吗啡依赖及戒断大鼠皮质m2,m5AChR mRNA及蛋白表达的影响。结果:(1)慢性吗啡作用使皮质m2,m5AChR mRNA及m2AChR蛋白表达明显增加(P<0.01);(2)纳洛酮催促戒断使m2,m5AChR mRNA及蛋白表达进一步升高(P<0.01);(3)PNS可以剂量依赖性地抑制纳洛酮催促戒断所引起的AChR mRNA及蛋白表达的增强。结论:PNS可通过抑制m2,m5AChR mRNA及蛋白的表达缓解吗啡戒断症状。     

洛非西定抑制吗啡依赖大鼠蓝斑Fos蛋白的表达

目的·· :研究洛非西定控制阿片类戒断症状的分子机理。方法·· :采用连续5dip 吗啡,建立大鼠吗啡依赖模型 ,给予洛非西定干预、纳洛酮促瘾后观察戒断症状 ,并取桥脑蓝斑切片 ,进行Fos蛋白免疫细胞化学实验。结果··:吗啡依赖大鼠经洛非西定干预后 ,由纳洛酮催促的戒断症状明显低于未经洛非西定处理组 ;经洛非西定干预后 ,蓝斑Fos蛋白免疫反应活性明显低于未经洛非西定处理组 ;但较盐水对照组高。结论·· :洛非西定能抑制吗啡依赖大鼠戒断症状以及蓝斑Fos蛋白的表达。     

海马 GDNFmRNA的表达参与大鼠吗啡戒断反应

目的：观察吗啡戒断大鼠侧脑室胶质细胞源性神经营养因子（glial cell derived neurotrophic factor，GDNF）反义寡脱氧核苷酸注射后对海马GDNFmRNA表达的影响。方法：SD大鼠侧脑室立体定位，皮下注射吗啡建立吗啡依赖大鼠模型，侧脑室微注射GDNF有义和反义寡脱氧核苷酸，纳洛酮催促戒断，应用原位杂交方法检测海马GDNFmRNA的表达。结果：侧脑室注射GDNF反义寡脱氧核苷酸能显著抑制大鼠吗啡戒断症状评分（n=t,p〈0．05）。吗啡依赖大鼠海马CA2区GDNFmRNA表达较对照组显著增加（n=3，P〈0．05），CA1和CA3区变化不明显；吗啡依赖大鼠纳洛酮（4mg／kg，岫催促戒断后海马CA1、CA2和CA3区GDNFmRNA表达较依赖组有增加趋势，但均没有显著差异心=3，P〉0．05）；吗啡依赖大鼠纳洛酮激发前24h侧脑室注射GDNF反义寡脱氧核苷酸能显著抑制吗啡依赖大鼠依赖和戒断后CA2区GDNFmRNA表达的增加（n=3，p〈0．05），而CA1和CA3区与戒断组大鼠相应区域相比没有差异；吗啡依赖大鼠纳洛酮激发前24h侧脑室注射GDNF有义寡脱氧核苷酸与戒断组大鼠相比海马CA1、CA2和CA3区GDNFmRNA表达均没有显著性差异（n=3，P〉0．05）。结论：在转录水平，海马CA2区GDNF表达的变化在吗啡依赖和戒断中可能起重要作用。     

The spinal nitric oxide involved in the inhibitory effect of midazolam on morphine-induced analgesia tolerance

Previous studies had shown that pretreatment with midazolam inhibited morphine-induced tolerance and dependence. The present study was to investigate the role of spinal nitric oxide (NO) in the inhibitory effect of midazolam on the development of morphine-induced analgesia tolerance. Subcutaneous injection of 100 mg/kg morphine to mice caused an acute morphine-induced analgesia tolerance model. To develop chronic morphine tolerance in mice, morphine was injected for three consecutive days (10, 20, 50 mg/kg sc on Day 1, 2, 3, respectively). In order to develop chronic tolerance model in rats, 10 mg/kg of morphine was given twice daily at 12 h intervals for 10 days. Midazolam was intraperitoneally injected 30 min prior to administration of morphine. Tail-flick test, hot-plate and formalin test were conducted to assess the nociceptive response. Immunocytochemistry, histochemistry and western blot were performed to determine the effect of midazolam on formalin-induced expression of Fos protein, nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) and nitric oxide synthase (NOS) in chronic morphine-tolerant rats, respectively. The results showed that pretreatment with midazolam significantly inhibited the development of acute and chronic morphine tolerance in mice, which could be partially reversed by intrathecal injection of NO precursor L-arginine (L-Arg). In chronic morphine-tolerant rats, pretreatment with midazolam significantly decreased the formalin-induced expression of Fos and Fos/NADPH-d double-labeled neurons in the contralateral spinal cord and NADPH-d positive neurons in the bilateral spinal cord. Both inducible NOS (iNOS) and neuronal NOS (nNOS) protein levels in the spinal cord were significantly increased after injection of formalin, which could be inhibited by pretreatment with midazolam. The above results suggested that the decrease of the activity and expression of NOS contributed to the inhibitory effect of midazolam on the development of morphine tolerance.     

Cross talk between nitric oxide and ERK1/2 signaling pathway in the spinal cord mediates naloxone-precipitated withdrawal in morphine-dependent rats

Our recent study has shown activation of spinal extracellular signal-regulated kinase-1 and -2 (ERK1/2), a member of the mitogen-activated protein kinase (MAPK) family, contributes to naloxone-precipitated withdrawal and withdrawal-induced spinal neuronal sensitization in morphine-dependent rats. However, the mechanism and significance of the spinal ERK1/2 activation during morphine dependence and withdrawal remain unknown. In this study, we reported that intrathecal (i.t.) pretreatment with either the non-selective nitric oxide synthase (NOS) inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME), neuronal NOS (nNOS) inhibitor 7-nitro indazole (7-NI), or the inducible NOS (iNOS) inhibitor aminoguanidine (AG), could reduce morphine withdrawal-induced increase of phospho-ERK1/2 (pERK1/2) expression in the rat spinal cord. On the other hand, attenuation of the spinal ERK phosphorylation by the MAPK kinase (MEK) inhibitor U0126 also could inhibit the increase of nNOS and iNOS expression in the spinal cord of morphine withdrawal rats. Inhibitory expression of pERK1/2 by i.t. NOS inhibitor L-NAME, 7-NI or AG and of nNOS and iNOS by i.t. U0126 in the spinal cord were accompanied by decreased scores of morphine withdrawal and the inhibited spinal Fos protein (a maker for neuronal excitation or activation) expression induced by morphine withdrawal. These findings suggest cross talk between nitric oxide (NO) and the ERK1/2 signaling pathway mediates morphine withdrawal and withdrawal-induced spinal neuronal sensitization in morphine-dependent rats.     

毒蕈碱和NMDA受体拮抗剂对吗啡依赖大鼠脊髓和脑干前脑啡肽原和前强啡肽原mRNA表达的影响

目的　观察毒蕈碱 (M)受体拮抗剂对吗啡依赖大鼠脊髓和脑干前脑啡肽原 ( preproenkephalin ,PPE)和前强啡肽原 ( preprodynorphin ,PPD)mRNA表达的影响。 方法　本文利用逆转录聚合酶链反应 (RT PCR) ,以 β actinmRNA为内标检测了PPE和PPDmRNA。结果　吗啡依赖大鼠脊髓和脑干PPE基因表达和正常大鼠相比都略有增加 ,吗啡依赖大鼠注射纳洛酮激发戒断反应后 ,脊髓PPE基因表达增加 ,而脑干中变化不明显。吗啡依赖大鼠脊髓和脑干PPD基因表达都低于正常大鼠组 ,吗啡戒断反应时脊髓PPD基因表达在 1h变化不明显 ,2h时增加到峰值 ,4h时仍高于依赖组 ,而脑干强啡肽基因表达在 1h、2h和 4h时都明显减少。经M受体拮抗剂甲基东莨菪碱和M1拮抗剂 pirenzepine处理后大鼠脊髓和脑干PPE和PPD基因表达较戒断 1h组有不同程度的增加 ;经NMDA受体拮抗剂MK 80 1处理后 ,脊髓和脑干中PPE基因较戒断组 1h无明显差异 ,脊髓和脑干PPD基因表达较戒断组明显增加 ;而经NOS抑制剂L N 硝基精氨酸甲酯 (L NAME)处理后大鼠脊髓和脑干PPE基因表达较戒断 1h组有不同程度的增加 ,脊髓和脑干PPD基因表达变化不明显。脊髓和脑干中 β actin基因表达在各处理组之间没有差别。结论　M受体拮抗剂、NMDA受体拮抗剂和NOS抑制剂在吗啡戒断反应时增加     

CNQX对伤害性刺激隐神经诱发大鼠脊髓Fos蛋白表达的影响

目的 探讨伤害性刺激隐神经（SN）能否诱发脊髓神经元Fos蛋白表达及发生机制.方法 应用免疫组化方法观察伤害性刺激SN和尾静脉注射谷氨酸非NMDA受体拮抗剂（CNQX）后诱发脊髓神经元Fos蛋白表达的变化.结果 伤害性刺激SN后,诱导脊髓神经元Fos蛋白表达显著增强,CNQX拮抗了Fos蛋白表达的显著增强.结论 以伤害性刺激SN模拟躯体痛后,CNQX拮抗了伤害性刺激SN引起的脊髓神经元Fos蛋白表达的显著增加,表明非NMDA受体在躯体痛的调控中起到了重要的作用.     

NMDA受体介导皮下注射福尔马林诱发的大鼠脊髓Fos蛋白的表达

AIM: To examine the effects of N-methyl-D-aspartate (NMDA) and non-NMDA receptors on noxious stimulation-induced Fos expression in the rat spinal cord. METHODS: Formalin (2%) was injected s.c. into one hindpaw of the rat. Fos expression was exhibited by immunocytochemical technique. RESULTS: Two hours after s.c. formalin, Fos-like immunoreactive (FLI) neurons were distributed mainly in medial part of the lamina I and the outer lamina II of the ipsilateral dorsal horn. dl-2-Amino-5-phosphonovalerate (APV) administered intrathecally (10 microL, 0.01, 0.1, or 1 g.L-1) before injection of formalin into a hindpaw reduced the number of FLI neurons dose-dependently in the dorsal horn (P < 0.01), while 6,7-dinitroquinoxaline-2, 3(1H,4H)-dione (DNQX) (1 g.L-1) was ineffective. CONCLUSION: NMDA receptor mediated noxious stimulation-induced Fos expression in the rat spinal cord.     

Spinal administration of lipoxygenase inhibitors suppresses behavioural and neurochemical manifestations of naloxone-precipitated opioid withdrawal

1. This study investigated the role of spinal lipoxygenase (LOX) products in the induction and expression of opioid physical dependence using behavioural assessment of withdrawal and immunostaining for CGRP and Fos protein expression in the spinal cord. 2. Administration of escalating doses (5-50 mg kg-1; i.p.) of morphine for 5 days markedly elevated CGRP-like immunoreactivity in the dorsal horn of the rat spinal cord. Naloxone (2 mg kg-1; i.p.) challenge precipitated a robust withdrawal syndrome that depleted CGRP-like immunoreactivity and increased the number of Fos-like immunoreactive neurons in the dorsal horn. 3. Intrathecal administration of NDGA (10, 20 microg), a nonselective LOX inhibitor, AA-861 (1.5, 3 microg), a 5-LOX selective inhibitor, or baicalein (1.4, 2.8 microg), a 12-LOX selective inhibitor, concurrently with systemic morphine for 5 days or as a single injection immediately preceding naloxone challenge, blocked the depletion of CGRP-like immunoreactivity, prevented increase in the number of Fos-like immunoreactive neurons in the dorsal horn, and significantly attenuated the morphine withdrawal syndrome. 4. The results of this study suggest that activity of LOX products, at the spinal level, contributes to the expression of opioid physical dependence, and that this activity may be expressed through increased sensory neuropeptide release.