牙髓炎症中三叉神经节和三叉神经脊束核尾侧亚核NOS的变化

目的：探讨ＮＯ与牙髓炎性痛过敏的关系。方法：应用组织化学方法，研究了牙髓炎症不同阶段三叉神经节和三叉神经脊束核尾侧亚核ＮＯ合酶（ｎｉｔｒｉｃｏｘｉｄｅｓｙｎｔｈａｓｅ，ＮＯＳ）阳性神经元的变化。结果：在与传递伤害性信息有关的三叉神经节中、小型细胞和三叉神经脊束核尾侧亚核的Ⅰ、Ⅱ层均有ＮＯＳ阳性神经元的出现；三叉神经节在牙髓炎症１４ｄ组、２１ｄ组，三叉神经脊束核尾侧亚核在炎症１４ｄ组阳性神经元均有明显增多。结论：ＮＯ可能参与了牙髓慢性伤害性刺激有关的痛觉过敏的外周和中枢机制     

伤害性刺激大鼠切牙引起三叉神经脊束核尾侧亚核内Fos的表达

在甲氧氟烷麻醉下，给大鼠切牙不同形式的伤害性刺激．动物存活２ｈ后，用ＡＢＣ法检查大鼠三叉神经脊束核尾侧亚核神经元的Ｆｏｓ（原癌基因ｃ－ｆｏｓ表达的蛋白产物）．结果发现，几种伤害性刺激均引起同侧三叉神经脊束核尾侧亚核神经元的Ｆｏｓ表达．以机械穿髓为最多，依次是化学刺激、热刺激和电刺激．提示不同的刺激引起牙髓痛反应程度可能不同，其结果可为牙痛研究提供较为客观的指标，并可用以探索牙痛的的中枢调制和传导途径．     

牙髓炎性和机械损伤性伤害刺激诱导大鼠Vc内Fos的表达 …

目的：探讨并比较急性牙髓炎和牙齿开髓刺激后不同时间点，三叉神经脊束核尾侧亚核（ＶＣ）内兴奋神经元的分布。方法：分别制备大鼠急性牙髓炎和牙齿开髓模型，应用免疫组织化学染色方法观察大鼠牙齿１、２、４ｈ和急性牙髓炎２、４ｈ组ＶＣ内Ｆｏｓ免疫阳性神经元的分布。结果：Ｇ工髓各组Ｆｏｓ免疫阳性神经元集中分布在ＶＣ支背侧区；急性牙髓炎２ｈ组，主要分布在ＶＣ浅层背侧区，４ｈ组，ＶＣ各层内可见Ｆｏｓ免疫阳性神经元的     

YDM—1牙科电子麻醉仪诱发Vc内Fos表达

目的：探讨面部ＴＥＮＳ后,三叉神经脊束核尾侧亚核（Ｖｃ） 内兴奋细胞的分布。方法：利用免疫组织染色化学方法观察正常以及面部ＴＥＮＳ后１ 、２、４ｈ 大鼠Ｖｃ 内Ｆｏｓ 免疫阳性神经元的分布。结果：ＴＥＮＳ后１ｈ,Ｆｏｓ 免疫阳性神经元集中分布在Ｖｃ 浅层背侧区,ＴＥＮＳ后２ｈ ,内层也出现少量Ｆｏｓ 免疫阳性神经元,ＴＥＮＳ后４ｈ ,Ｖｃ 各层内可见Ｆｏｓ 免疫阳性神经元的分布。结论：Ｖｃ 浅层和内层的神经元均参与ＴＥＮＳ反应,早期主要是Ｖｃ 浅层背侧区神经元。     

牙髓炎性和机械损伤性伤害刺激诱导大鼠Vc内Fos表达的比较研究

目的：探讨并比较急性牙髓炎和牙齿开髓刺激后不同时间点,三叉神经脊束核尾侧亚核（Ｖｃ）内兴奋神经元的分布。方法：分别制备大鼠急性牙髓炎和牙齿开髓模型,应用免疫组织化学染色方法观察大鼠牙齿开髓后１、２、４ｈ 和急性牙髓炎２ 、４ｈ 组Ｖｃ 内Ｆｏｓ 免疫阳性神经元的分布。结果：开髓各组Ｆｏｓ 免疫阳性神经元集中分布在Ｖｃ 浅层背侧区;急性牙髓炎２ｈ 组,主要分布在Ｖｃ 浅层背侧区;４ｈ 组,Ｖｃ 各层内可见Ｆｏｓ 免疫阳性神经元的分布。结论：牙齿次机械损伤和炎症刺激可以兴奋Ｖｃ 内不同区域的神经元,牙髓炎组Ｖｃ 内神经元兴奋有时间上的相继性。     

实验性牙移动后三叉神经脊束核尾侧亚核CGRP的研究

目的：研究实验性牙移动过程中，三叉神经脊束核尾侧亚核(Vc)内降钙素基因相关肽(CGRP)的改变。方法：在大鼠左侧上颌第一、二磨牙间塞入一弹性橡皮圈模拟临床正畸加力状态。于不同加力时间点对三叉神经脊束核尾侧亚核进行CGRP免疫组化染色。结果：加力后6h和24h，实验侧三叉神经脊束核尾侧亚核CGRP样纤维明显少于对侧；施力3d后Vc浅层中CGRP样阳性终末与对照侧无明显差异，加力后1w大于对侧，2w时恢复至对侧水平。结论：实验性牙移动引起CGRP在三叉神经脊束核尾侧亚核释放。     

三叉神经脊束核在口面痛传导中的作用

三叉神经脊束核位于延髓段，延髓的外侧及三叉神经脊束的内侧，解剖学上证实三叉神经脊束核是口腔颌面部信息向中枢传导的第一门户，目前认为三叉神经脊束核尾侧亚核及相邻区域是参与口面部伤害信息传导的重要部位，机体内许多神经生化物质包括P物质，降钙素基因相关肽，阿片肽及肽类，乙酰胆碱，单胺类，氨基酸类等物质参与三叉神经脊束核区域口面部伤害信息的传递过程。     

三叉神经脊束核尾侧亚核星形胶质细胞对咬合创伤的反应

目的：观察大鼠咬合创伤后三叉神经脊束核尾侧亚核（Sp5C）内星形胶质细胞的反应,探讨星形胶质细胞在咬合创伤中的作用。方法：用方丝将大鼠左侧上颌第一磨牙咬合抬高0.5mm,形成左侧磨牙早接触的创伤咬合。粘固后1,3,7,14,30d取三叉神经脊束核尾侧亚核,免疫荧光染色观察星形胶质细胞在三叉神经脊束核尾侧亚核的表达变化。结果：对照组见少量胶质原纤维酸性蛋白（GFAP）阳性星形胶质细胞呈散在分布,咬合创伤3d时,实验侧GFAP阳性面积增加,荧光强度增强;7d时达到高峰,14d组GFAP阳性反应产物开始减少。结论：咬合创伤激活了星形胶质细胞,提示星形胶质细胞在口颌面痛产生及维持中发挥作用。     

蟾酥制剂对大鼠三叉神经节及三叉神经脊束核尾侧亚核中P物质的影响

目的：比较分析蟾酥制剂作用于牙髓后，三叉神经节(TG)和三叉神经脊束核尾侧亚核(Vc)内P物质(SP)的变化。方法：利用免疫组织化学染色方法，观察大鼠牙齿开髓封药0、1、2、4、6、24h后TG和Vc内sP的变化。结果：开髓1h时TG内阳性神经元的数目少于对照侧，4h后阳性神经元数量逐渐增多，接近正常。封药1h后Vc内密度低于对照侧，4h时密度明显高于对照侧，随后逐渐减低，至24h后已与对照侧密度一致。结论：蟾酥制剂可抑制TG内SP的合成和释放，Vc内三叉神经末梢释放SP减少。     

正畸牙齿移动刺激信息传导通路的动物实验研究

研究丘脑腹后内侧核（ＶＰＭ）是否接受来自三叉神经脊核尾业核传入的牙齿移动性刺激信息,从而探讨牙齿动引起的伤害性刺激信息在中枢神经系统内的感觉传导通路。方法：用微量注射器将２％荧光金ＦＧ）注入大鼠ＶＰＭ４－６ｄ后,进行对侧的实验性牙齿移动２ｈ,用ＦＯＳ蛋白免疫化方法观察Ｖｃ内神经元对ｃ－ｆｏｓ的表达以及是否存在ＦＧ与ＦＯＳ双重阳性的神经元。结果ＦＯＳ阳性神经元密集分布于同侧Ｖｃ浅层,呈带状,背外侧居     

Functional properties of tooth pulp neurons responding to thermal stimulation

The response properties of tooth pulp neurons that respond to noxious thermal stimulation of the dental pulp have been not well-studied. The present study was designed to characterize the response properties of tooth pulp neurons to noxious thermal stimulation of the dental pulp. Experiments were conducted on 25 male ferrets, and heat stimulation was applied by a computer-controlled thermode. Only 15% of tooth pulp neurons (n = 39) responded to noxious thermal stimulation of the teeth. Tooth pulp neurons were found in both the superficial and deep nuclear regions of the subnucleus caudalis (Vc) and in the interface between the nucleus caudalis and interpolaris (Vc/Vi). Thirty-seven neurons had cutaneous receptive fields and were classified as either NS (16) or WDR (21) neurons. Repeated heat stimulation of the dental pulp sensitized and increased the number of electrically evoked potentials of tooth pulp neurons. These results provide evidence that both the Vc and Vc/Vi regions contain neurons that respond to noxious thermal stimulation of the dental pulp, and that these cells may contribute to the sensitization process associated with symptomatic pulpitis.     

牙髓炎不同阶段P2X受体家族在大鼠脑干中的表达变化研究

目的:研究牙髓炎不同阶段P2X受体家族在大鼠脑干中的表达变化。方法::本实验在大鼠左上颌第一磨牙颌面开髓,并暴露于口腔菌群环境,诱导牙髓炎症。取牙髓炎症第1天、第3天、第7天和第28天时,大鼠双侧脑干的三叉神经脊束核尾端亚核(Vc)和丘脑的腹后中核(VPM),采用免疫组化和免疫荧光方法观察P2X受体家族(P2X1-7受体)的表达模式。结果:实验观察到牙髓炎症第1、3、7天显示急性牙髓炎症的组织学表现,其中第3天最为典型,而第28天显示牙髓坏死和慢性根尖周炎的组织学表现;P2X1-6受体在Vc和VPM中均表达在神经元的胞浆中,而P2X7表达在Vc和VPM中在小胶质细胞中;P2X2,P2X4和P2X7受体在急性牙髓炎症期在同侧Vc中的表达增加;P2X1-5和P2X7的表达都在双侧VPM中均上升,开髓3 d时,对侧VPM中P2X1-5和P2X7的平均表达面积显著高于同侧。结论:除P2X6受体持续高表达外,P2X1-5和P2X7受体均可受到牙髓炎症的诱导,在Vc和VPM中表达增高。     

Development of the pioneer sympathetic innervation into the dental pulp of the mouse mandibular first molar

OBJECTIVE: Our goal was to study the development of pioneer sympathetic innervation of dental pulp of mouse mandibular first molar. DESIGN: We used double fluorescent immunohistochemistry with tyrosine hydroxylase (TH) and anti-medium-chain neurofilament (2H3) antibodies to detect sympathetic and sensory nerve fibres. Serial sections of whole teeth from postnatal days (PN) 0-14, trigeminal and sympathetic superior cervical ganglia of PN 15 mice were examined with confocal microscope. RESULTS: There were two main findings. The unexpected finding was that 2H3 antibody was specific only for sensory nerve fibres and neurons and failed to stain either sympathetic nerve fibres or neurons. The main finding was that although both sympathetic and sensory nerve fibres were already seen near the tooth germ at the newborn stage, the pioneer sympathetic nerve fibres were first observed in the dental pulp only after the onset of root formation on day 9, in contrast to sensory nerve fibres which entered the tooth already on day 4. CONCLUSION: Pioneer sympathetic innervation of dental pulp starts on postnatal day 9 and follows sensory innervation. This indicates differential developmental regulation of the initial sensory and sympathetic innervation of teeth and provides essential background data for further studies on the molecular regulation of pulp innervation.     

Effects of pre-emptive morphine, ibuprofen or local anesthetic on fos expression in the spinal trigeminal nucleus following tooth pulp exposure in the rat

In the present study, we used Fos expression as an index of nociceptive input to the spinal trigeminal nucleus after exposure of the coronal pulp tissue of maxillary right first molars and examined the effects of pretreatment with an opioid, a nonsteroidal anti-inflammatory drug or a local anesthetic before pulp exposure. Exposure of the tooth pulp produced a significant increase in Fos-like immunoreactivity in the superficial laminae of subnucleus caudalis; pretreatment with a control infiltration injection of saline directly above the maxillary molar 30 min before pulp exposure had no effect on Fos expression. Pretreatment with morphine 30 min before pulp exposure dose-dependently (2.5, 5, and 10 mg/kg subcutaneously) reduced Fos expression in subnucleus caudalis whereas pretreatment with ibuprofen (10-100 mg/kg subcutaneously) did not significantly affect Fos expression. Local anesthetic pretreatment was effective in reducing Fos expression only for the long acting bupivacaine; lidocaine without and with epinephrine (1:100,000) failed to significantly affect Fos expression. These results suggest that pre-emptive opioid treatment can decrease postoperative central nervous system changes associated with tooth pulp injury, and therefore, may decrease postoperative pain. Given the effects of local anesthetic on Fos expression, a combination of long acting local anesthetic with pre-emptive opioid would likely be most efficacious in decreasing postoperative dental pain.     

Expression of Piezo2 in the Dental Pulp,Sensory Root,and Trigeminal Ganglion and Its Coexpression with Vesicular Glutamate Transporters

IntroductionInformation on the type of vesicular glutamate transporter (VGLUT) that is expressed in the Piezo2-positive (Piezo2+) neurons in the trigeminal ganglion (TG) and on the type of Piezo2+ axons and their distribution in the dental pulp is important for understanding dental pain elicited by mechanical stimuli and developing new therapeutic strategies.MethodsWe examined the expression of Piezo2 and its coexpression with VGLUT1 and VGLUT2 in rat TG, the sensory root, and human dental pulp using light and electron microscopic immunohistochemistry and quantitative analysis.ResultsVGLUT1 and VGLUT2 were expressed in the TG neurons. Piezo2 was expressed in axons of all types but primarily in small myelinated (Aδ) axons in the sensory root. In the dental pulp, Piezo2 was expressed densely in the numerous axons that form a plexus in the peripheral pulp. Piezo2+ axons in the peripheral pulp were mostly unmyelinated, and Piezo2 immunoreactivity was often concentrated near the axolemma, suggesting that it may represent functional receptors.ConclusionsThese findings suggest that VGLUT1 and VGLUT2 are involved in the glutamate signaling in Piezo2+ neurons, Piezo2 may be primarily activated by noxious mechanical stimuli, and Piezo2-mediated dental mechanotransduction may be primarily elicited in the peripheral pulp.     

Activation of trigeminal intranuclear pathway in rats with temporomandibular joint inflammation

We examined the anatomical connections of trigeminal neurons between the trigeminal subnuclei interpolaris/caudalis (Vi/Vc) transition and caudal subnucleus caudalis/upper cervical dorsal horn (Vc/C(1,2)) zones in rats, using the fluorogold (FG) retrograde tracing method combined with Fos expression, a marker of neuronal activation, following temporomandibular joint (TMJ) inflammation. The head withdrawal threshold was also measured in rats 3 days after complete Freund's adjuvant (CFA)-induced TMJ inflammation. The head withdrawal threshold on the inflamed side was significantly decreased after CFA injection into the TMJ. FG was injected into the Vi/Vc transition zone and retrogradely labeled FG-positive cells were observed in the Vc/C(1,2) region. Numerous Fos protein-expressing cells were present both in the Vi/Vc transition zone and in the laminated Vc/C(1,2) zone. A population of cells was double-labeled with Fos and FG in the Vc/C(1,2) zone. Fos/FG cells were only observed in the deep laminae of the Vc/C(1,2) zone. These findings suggest that Vi/Vc transition zone activity is modulated by activation of the caudal laminated zone after orofacial tissue injury.     

DKK1对脂多糖感染人牙髓细胞生物学行为的影响

目的:研究DKK1对脂多糖(lipopolysaccharide,LPS)感染人牙髓细胞生物学行为的影响.方法:使用改良酶组织块法分离培养人牙髓细胞并通过免疫荧光染色鉴定细胞来源;通过细胞计数试剂盒(CCK-8)、Transwell实验、茜素红染色、荧光定量PCR等实验检测DKK1对LPS感染人牙髓细胞的生物学行为的变...     

The effect of inflammation on Fos expression in the ferret trigeminal nucleus

We have previously carried out detailed characterization and identification of Fos expression within the trigeminal nucleus after tooth pulp stimulation in ferrets. The aim of this study was to determine the effect of pulpal inflammation on the excitability of central trigeminal neurons following tooth pulp stimulation. Adult ferrets were prepared under anesthesia to allow tooth pulp stimulation, recording from the digastric muscle, and intravenous injections at a subsequent experiment. In some animals, pulpal inflammation was induced by introducing human caries into a deep buccal cavity. After 5 d, animals were re-anaethetized, and the teeth were stimulated at 10 times the threshold of the jaw-opening reflex. Stimulation of all tooth pulps induced ipsilateral Fos in the trigeminal subnuclei caudalis and oralis. All non-stimulated animals showed negligible Fos labeling, with no differences recorded between inflamed and non-inflamed groups. Following tooth pulp stimulation, Fos expression was greater in animals with inflamed teeth than in animals with non-inflamed teeth, with the greatest effect seen in the subnucleus caudalis. These results suggest that inflammation increases the number of trigeminal brainstem neurons activated by tooth pulp stimulation; this may be mediated by peripheral or central mechanisms.     

牙髓血管酶活性增龄改变的研究

作者对４２例１０～７０岁的正常牙髓血管的碱性磷酸酶（Ａｌｋａｌｉｎｅｐｈｏｓｐｈａｔａｓｅ，ＡＫＰ酶）、三磷酸腺苷酶（Ａｄｅｎｏｓｉｎｅｔｒｉｐｈｏｓｐｈａｔａｓｅ，ＡＴＰ酶）组织化学分布和增龄性改变进行了定性和定量分析。目的是通过酶组织化学技术，研究牙髓血管的增龄改变，为临床治疗牙体牙髓病，提供理论依据。结果表明，随年龄增加，牙髓血管的ＡＫＰ酶和ＡＴＰ酶活性降低。１０～３０岁、３１～５０岁和５１～７０岁组的ＡＫＰ酶活性反应量分别为：４０．６２±１３．７９、３６．７５±９．７８、１９．２０±５．３５；ＡＴＰ酶活性反应量分别为：３３．００±１０．０９、２７．５３±１６．６０、２３．２７±５．０４。在牙髓血管中改变最大的是毛细血管内皮细胞。提示随年龄增加，牙髓组织的代谢能力减弱。此外，还观察到在造牙本质细胞下层的毛细血管随年龄增加而减少，造牙本质细胞层变薄。表明毛细血管与造牙本质细胞有密切关系。     

凝血酶受体在人牙髓组织和细胞中表达的免疫组化研究

目的：探讨凝血酶受体在人正常、炎症牙髓组织及体外培养的牙髓成纤维细胞中的表达及其意义。方法：体外培养人牙贿成纤维细胞,收集正常和炎症牙髓组织,采用免疫组织化学方法观察凝血酶受体在牙髓组织和细胞中的表达和分布。结果：体外培养的牙髓成纤维细胞可见受体强阳性表达,正常及炎症牙髓组织中成牙本质细胞层、牙髓细胞、血管内皮细胞均呈广泛的阳性表达,炎症区淋巴细胞、单核细胞、中性粒细胞染色为强阳性。结论：人牙髓组