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。     

咬合创伤大鼠Vc内sP和NMDAR1的表达

目的；观察大鼠咬合创伤后Vc内SP和NMDA受体亚单位1型（NMDAR1）表达的变化，分析咬合创伤后Vc内初级感觉神经元中枢端末梢的敏感化和传导机制。方法：应用免疫组织化学方法，观察咬合创伤大鼠，双测Vc内SP、NMDAR1表达的变化。结果：空白对照大鼠Vc内SP和NMDAR1免疫阳性结构为终末和纤维，主要分布在VcⅠ、Ⅱ两层，呈新月形染色弧。两侧分布对称，咬合创伤7d组，实验侧Vc内SP、NMDAR1表达均上调，灰度值与对照侧相比有显差异。咬合创伤15d组，实验侧Vc内SP、NMDAR1表达比对照侧高，但无显差异。咬合创伤30d，实验侧Vc内SP、NMDAR1免疫阳性结构在同一切片中左右密度不对称，有的切片实验侧密度大于对照侧，有的切片实验侧密度低于对照侧。结论：咬合创伤后，Vc内SP、NMDAR1的表达发生变化，提示咬合创伤后初级中枢发生敏感化，是咬合创伤导致口面部慢性疼痛的机制之一。     

急性牙髓炎致敏时Vc核c-fos蛋白的时程变化

目的:研究大鼠急性牙髓炎造成中枢致敏时三叉神经脊束核尾侧亚核(caudal part of spinaltrigeminal nucleus,Vc)内c-fos蛋白的变化情况。方法:建立大鼠急性牙髓炎模型,利用免疫组化实验检测不同时间点Vc核c-fos蛋白变化情况,采用单因素方差分析比较不同时间点的变化情况。结果:在封药后12h至24h,Vc核c-fos阳性神经元表达数目显著增多。结论:Vc内c-fos蛋白的变化时程与牙髓炎进展密切相关。     

咬合重建对大鼠三叉神经节P物质表达影响的研究

目的：研究咬合重建对大鼠三叉神经节P物质（substance P,SP）表达的影响。方法：Wistar雄性大鼠30只,随机分为3个实验组及相应的正常对照组,每组5只。实验组动物间断磨除右上、下颌磨牙牙冠至龈下,有2组分别第3周、第9周停止磨牙,任其自行萌出,恢复咬合关系。双侧三叉神经节（trigeminal ganglia,TG）切片行SP免疫组织化学反应（SABC法）。光镜观察拍片,并用Image Pro Plus5.1图像分析软件进行测定。结果与对照组对照。SPSS10.0软件行统计分析。结果：单侧咀嚼实验组咀嚼侧和非咀嚼侧TG内SP免疫阳性神经元百分比与对照组比较显著降低（P〈0.01,P〈0.05）,其非咀嚼侧明显低于咀嚼侧（P〈0.01）。早期恢复咬合实验组TG内免疫阳性神经元百分比与对照组比较无差别（P〉0.05）,其咀嚼侧与非咀嚼侧比较无差别（P〉0.05）。晚期恢复咬合实验组TG内免疫阳性神经元百分比与对照组比较显著降低（P〈0.01,P〈0.05）,其非咀嚼侧明显低于咀嚼侧（P〈0.05）。结论：早期恢复咬合关系TG内SP表达可恢复正常,晚期恢复咬合关系SP表达不能恢复正常,SP参与了单侧咀嚼引起的颞颌关节病的病理变化过程。     

牙髓损伤性刺激诱导大鼠三叉神经脊束尾侧亚核内P物质等多肽的表达

目的：比较、分析急性牙髓炎和牙齿开髓刺激后,三叉神经脊束核尾侧亚核（Ｖｃ）内Ｐ物质（ＳＰ）、降钙素基因相关肽（ＣＧＲＰ）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后１ｈ、２ｈ、４ｈ和急性牙髓炎２ｈ、４ｈ组Ｖｃ内ＳＰ、ＣＧＲＰ免疫阳性纤维的变化。结果：开髓１ｈ组实验侧与对照侧相比,ＳＰ、ＣＧＲＰ免疫阳性纤维减少,其余各组的实验侧与对照侧无显著差异。结论：两种刺激均引起Ｖｃ内三叉神经末梢释放ＳＰ、ＣＧＲＰ。     

牙髓损伤性刺激诱导大鼠三叉神经脊束尾侧亚核内P物质等 …

目的 比较，分析急性牙髓炎和牙齿开髓刺激后，三叉神经脊束核尾侧亚核（Ｖｃ）内Ｐ物质（ＳＰ）降钙素基因相关肽（ＣＧＲＰ）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后１ｈ，２ｈ４ｈ和急性牙髓炎２ｈ，４ｈ组Ｖｃ内ＳＰ，ＣＧＲＰ的免疫阳性纤维的变化，结果 开髓１ｈ组实验侧与对照侧相比，ＳＰ，ＣＧＲＰ免疫阳性纤维减少，其余各组的实验侧与对照侧无显著差异，结论：两种刺激均引起Ｖｃ的三叉神经末梢释放     

大鼠急性牙髓炎造成中枢致敏时三叉神经脊束核极间亚核和孤束核c-fos蛋白的时程变化

目的:研究大鼠急性牙髓炎造成中枢致敏时三叉神经脊束核极间亚核(interpolar part of spinal trigeminal nucleus,vi)和孤束核(nucleus tractus solitafius,NTS)内c-fos蛋白的变化情况.方法:建立大鼠急性牙髓炎模型,利用免疫组化实验检测不同时间点Vi核和NTS核c-fos蛋白的变化情况,采用单因素方差分析比较不同时间点的变化情况.结果:封药后12h至24h,Vi核c-los阳性神经元表达数目明显增多;而双侧NTS内的c-fos阳性神经元数目在6h时最多,随后逐渐减少.结论:延髓内c-fos蛋白的变化时程与牙髓炎进展密切相关.     

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     

咬合恢复对大鼠三叉神经节PPTA mRNA及其相应蛋白表达的影响

目的:研究咬合恢复对大鼠三叉神经节P物质(substance P,SP)及编码SP的前速激肽原A(PPTA)mRNA表达的影响.方法:Wistar雄性大鼠48只,随机分为3个实验组及相应的正常对照组,每组8只.实验组动物间断磨除右上、下颌磨牙牙冠至龈下,2组分别于第3、9周停止磨牙,任其自行萌出,恢复咬合关系.双侧三叉神经节(trigeminal ganglia,TG)切片行SP免疫组织化学反应(SABC法)和原位杂交反应.光镜观察摄片,并用Image Pro Plus 5.1图像分析软件进行测定.采用SPSS10.0软件包对数据进行统计学分析.结果:单侧咀嚼实验组咀嚼侧和非咀嚼侧TG内,SP阳性神经元百分比与对照组比较显著降低(P<0.01,P<0.05),其非咀嚼侧显著低于咀嚼侧(P<0.05);而PPTA mRNA阳性神经元百分比显著增高(P<0.01,P<0.05),其非咀嚼侧显著高于咀嚼侧(P<0.01).早期恢复咬合实验组TG内SP和PFTA mRNA阳性神经元百分比与对照组比较无显著差别(P>0.05),其咀嚼侧与非咀嚼侧比较无显著差别(P>0.05).晚期恢复咬合实验组TG内,SP和PPTA mRNA表达情况与单侧咀嚼实验组一致.结论:早期恢复咬合关系TG内SP和PPTA mRNA表达可恢复正常,晚期恢复咬合关系其表达不能恢复正常,SP和PPTA mRNA参与了单侧咀嚼引起的颞下颌关节病的病理变化过程.     

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。     

YDM—1牙科电子麻醉仪引起Vc内SP,CGRP的变化

目的： 分析面部ＴＥＮＳ后,三叉神经脊束核尾侧亚核（Ｖｃ）内Ｐ物质（ＳＰ）、降钙素基因相关肽（ＣＧＲＰ）的变化。方法：利用免疫组织化学染色方法观察大鼠面部ＴＥＮＳ后１、２、４ｈ,Ｖｃ 内ＳＰ、ＣＧＲＰ免疫阳性纤维的变化。结果：面部ＴＥＮＳ后１ｈ 实验侧与对照侧相比,ＳＰ、ＣＧＲＰ免疫阳性纤维减少,甚至有脱失现象,２ｈ组呈恢复趋势,４ｈ 组与对照侧无显著差异。结论：面部ＴＥＮＳ引起Ｖｃ 内三叉神经末梢大量释放ＳＰ、ＣＧＲＰ。     

牙髓损伤性刺激对牙髓组织中P物质等的影响

目的：比较和分析急性牙髓炎和牙齿开髓刺激后，牙髓组织中Ｐ物质（ＳＰ）、降钙素基因相关肽（ＣＧＲＰ）的变化。方法：利用免疫组织化学方法观察大鼠牙齿开髓后２ｈ、４ｈ和急性牙髓炎２ｈ、４ｈ组牙髓组织中ＳＰ、ＣＧＲＰ免疫阳性纤维的变化。结果：牙髓炎性及机械损伤性伤害刺激引起牙髓组织ＳＰ／ＣＧＲＰ免疫阳性纤维一致性变化。牙齿开髓及牙髓炎２ｈ、４ｈ组牙髓组织中ＳＰ、ＣＧＲＰ免疫阳性纤维减少。结论：两种刺激均引起牙髓组织内神经末梢释放ＳＰ、ＣＧＲＰ。     

蟾毒对狗牙髓CGRP免疫阳性神经纤维的影响

目的：观察狗牙髓直接封蟾毒后牙髓内降钙素基因相关肽免疫反应阳性（简称ＣＧＲＰ－ＩＲ）神经纤维的动态变化。方法：采用冰冻切片和免疫组织化学方法（ＡＢＣ法）。结果：封药１ｈ，蟾毒组及可卡因组其牙髓内ＣＧＲＰ－ＩＲ神经纤维在形态、染色及数量上无显著差别；封药４ｈ，蟾毒组牙髓内ＣＧＲＰ－ＩＲ神经纤维明显断裂、数量减少、染色变浅，而可卡因组则无明显变化。结论：蟾毒快速麻痹牙髓神经的作用机理可能为一种神经毒性作用     

Role of substance P and calcitonin gene-related peptide in the regulation of interleukin-8 and monocyte chemotactic protein-1 expression in human dental pulp

AIM: To determine whether leucocyte infiltration during neurogenic inflammation in the pulp is regulated by neuropeptides via inducing the release of proinflammatory chemokines interleukin-8 (IL-8) and monocyte chemotactic protein-1 (MCP-1) from human dental pulp. METHODOLOGY: Cultured primary pulp cells and pulp tissue explants were stimulated with substance P (SP) and/or calcitonin gene-related peptide (CGRP). IL-8 or MCP-1, secreted from cultured cells or produced in pulp explants, was analysed by enzyme-linked immunosorbent assay. RESULTS: Substance P induced IL-8 secretion from cultured pulp cells (approximately threefold increase over control, P < 0.05) and from pulp tissue explants (two- to three fold). SP only minimally to moderately induced MCP-1 (approximately two fold) in cultured pulp cells. While MCP-1 induction in cultured pulp cells was detected after 24 h of SP stimulation, no induction was observed in pulp tissue. CGRP did not induce IL-8, but moderately increased MCP-1 production (approximately three fold) in cultured pulp cells. There was no synergistic induction of MCP-1 by SP plus CGRP stimulation of pulp cells. CONCLUSIONS: Substance P is a stronger inducer of IL-8 production in dental pulp than CGRP. IL-8 is more strongly induced than MCP-1 by SP, suggesting a more important role for IL-8 than MCP-1 in leucocyte infiltration during neurogenic inflammation in dental pulp.     

Identification and neuropeptide content of trigeminal neurons innervating the rat gingivomucosal tissue

OBJECTIVES: The purpose of this study was to identify and characterise the neuropeptide content and the size of trigeminal ganglion (TG) neurons innervating the rat gingivomucosal tissue. DESIGN: Retrograde nerve tracer Fluorogold (FG) was injected into the gingiva (group 1, n=5) or applied into the gingival sulcus (group 2, n=5) of the first right maxillary molar. After 10 days, the ganglia were dissected and FG fluorescence was observed under UV light microscope. Expression of calcitonin gene-related peptide (CGRP) and substance P (SP) in FG-labelled neurons was investigated by immunohistochemistry. Cross-sectional areas of neuron cell bodies containing FG were determined. As a control group, approximately 1000 neuron cell bodies representing the entire TG neuron population was evaluated in five trigeminal ganglia. RESULTS: In group 1, the percentages of neurons containing CGRP (median 63%, range 48-72%) and SP (median 64%, range 54-64%) were significantly greater than in the control group (CGRP: median 43%, range 42-47% and SP: median 23%, range 21-27%). In group 2, only the percentage of neurons containing SP (median 50%, range 40-56%) was significantly greater than in the control group. FG-labelled neurons were predominantly small or medium sized (less than 1200 microm2). The neurons in the group 1 were significantly smaller than in group 2. In both experimental groups, immunopositive neurons were significantly smaller than immunonegative neurons. CONCLUSIONS: The majority of neurons in TG that innervate the rat gingivomucosa are small or medium sized and contain CGRP and SP.     

Calcitonin gene related peptide: a sensory transmitter in dental pulps?

Nerve fibers displaying calcitonin gene related peptide (CGRP) immunoreactivity occurred in dental pulps of several mammals, including man. The CGRP fibers were more numerous in the apical parts than in the coronal parts and were distributed around small blood vessels as well as in the pulpal stroma without any obvious relation to blood vessels. The trigeminal, spinal and jugular-nodose ganglia harbored a moderate supply of CGRP immunoreactive perikarya and nerve fibers. Immunocytochemic double staining revealed the coexistence of CGRP and SP in a population of perikarya in the sensory ganglia and suggested coexistence of the two peptides in perivascular nerve fibers in the cat dental pulp. The cervical sympathetic ganglia did not contain CGRP-immunoreactive perikarya. Cervical sympathectomy (studied in the guinea-pig and rat) did not affect the frequency or distribution of pulpal CGRP fibers. The distribution of CGRP fibers within the dental pulp and the presence of CGRP perikarya in sensory ganglia known to supply the dental pulps indicate that the pulpal CGRP fibers are sensory in nature and that CGRP together with SP may participate in the regulation of local blood flow and the response to local inflammation.     

Calcitonin gene related peptide: a sensory transmitter in dental pulps?

Abstract — Nerve fibers displaying calcitonin gene related peptide (CGRP) immunoreactivity occurred in dental pulps of several mammals, including man. The CGRP fibers were more numerous in the apical parts than in the coronal parts and were distributed around small blood vessels as well as in the pulpal stroma without any obvious relation to blood vessels. The trigeminal, spinal and jugular-nodose ganglia harbored a moderate supply of GGRP immunoreactive perikarya and nerve fibers. Immunocytochemic double staining revealed the coexistence of CGRP and SP in a population of perikarya in the sensory ganglia and suggested coexistence of the two peptides in perivascular nerve fibers in the cat dental pulp. The cervical sympathetic ganglia did not contain CGRP-immnunoreactive perikarya. Cervical sympathectomy (studied in the guinea-pig and rat) did not affect the frequency or distribution of pulpal CGRP fibers. The distribution of CGRP fibers within the dental pulp and the presence of CGRP perikarya in sensory ganglia known to supply the dental pulps indicate that the pulpal CGRP fibers are sensory in nature and that CGRP together with SP may participate in the regulation of local blood flow and the response to local inflammation.     

The effect of capsaicin on substance P expression in pulp tissue inflammation

AIM: To evaluate the effect of capsaicin on substance P (SP) expression during induced inflammation in rat pulp tissue. METHODOLOGY: Radioimmunoanalysis was used to measure SP levels in 36 mandibular molar pulps taken from six Wistar rats. Twelve samples were obtained from healthy pulps and used as negative control group. Another 12 samples were obtained after inducing inflammation with mechanical pulp exposure; these were used as the positive control group. Capsaicin was infiltrated into the inferior dental nerve in the experimental group and 12 samples were obtained after mechanical pulp exposure. RESULTS: The lowest SP expression was found in mechanically exposed pulps where capsaicin pretreatment had been carried out (0.028 ng mL(-1)), followed by healthy pulps (0.302 ng mL(-1)). The highest SP expression was found in mechanically exposed pulps with no capsaicin pretreatment (124 ng mL(-1)). The Kruskal-Wallis test showed statistically significant differences between the groups (P < 0.001). CONCLUSION: Inferior dental nerve infiltration with capsaicin reduces SP expression in dental pulp tissue in rats.