Pergamon-Elsevier Science Ltd.Acta Medica Okayama0016-703768242004A theoretical interpretation of the chemical shift of Si-29 NMR peaks in alkali borosilicate glasses51035111ENTokuroNanbaMitsunoriNishimuraYoshinariMiuraIn Si-29-NMR, it has so far been accepted that the chemical shifts of Q(n) Species (SiO4 units containing n bridging oxygens) were equivalent between alkali borosilicate, and boron-free alkali silicate classes. In the sodium borosilicate glasses with low sodium content. however. a contradiction was confirmed in the estimation of alkali distributions B-11 NMR suggested that Na ions were entirely distributed to berate groups to form BO4 units, whereas a -90 ppm component Was also observed in Si-29-NMR spectra, which has been attributed to Q(3) species associated with a nonbridging oxygen (NBO). Then. cluster molecular orbital calculations were performed to interpret the -90 ppm component in the borosilicate, glasses. It Was found that a silicon atom which had two tetrahedral borons (B4) as its second nearest neighbors was similar in atomic charge and Si2p energy to the Q(3) species in boron-free alkali silicates. Unequal distribution of electrons in Si-O-B4 bridging bonds was also found. where much electrons Were localized oil the Si-O bonds. It was finally concluded that the Si-O-B4 bridges with narrow bond angle were responsible for the -90 ppm Si-29 component in the borosilicate glasses. There still remained another interpretation: the Q(3) species were actually present in the glasses. and NBOs in the Q(3) species were derived from the tricluster groups. such as (O3Si)O(BO3)(2). In the classes With low sodium content. however. it was concluded that the tricluster groups were not so abundant to contribute to the -90 ppm component.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0008-62234782009The use of graphite oxide to produce mesoporous carbon supporting Pt, Ru, or Pd nanoparticles21202124ENKazumaGotohKojiKawabataEijiFujiiKunimitsuMorishigeTaroKinumotoYukiMiyazakiHiroyukiIshidaMesoporous carbon having platinum, ruthenium or palladium nanoparticles on exfoliated graphene sheets were produced from graphite oxide (GO) and metal complexes. The Pt included carbon was made by heating of the intercalation compound including tetraammineplatinum (II) chloride monohydrate. Samples having Ru or Pd are producible by heating in nitrogen gas atmosphere using hexaammineruthenium (III) chloride or tetraamminepalladium (II) chloride monohydrate instead of Pt complex. The particle sizes of platinum, ruthenium, and palladium were, respectively, 1–3, 1–2, and 3–7 nm. The platinum- or palladium-containing sample showed catalytic activity for oxygen reduction.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science LtdActa Medica Okayama0045-65356462006Alkaline hydrothermal treatment of brominated high impact polystyrene (HIPS-Br) for bromine and bromine-free plastic recovery10211025ENMihaiBrebuThalladaBhaskarAkinoriMutoYusakuSakata<p>A method to recover both Br and Br-free plastic from brominated flame retardant high impact polystyrene (HIPS-Br) was proposed. HIPS-Br containing 15% Br was treated in autoclave at 280℃ using water or KOH solution of various amounts and concentrations. Hydrothermal treatment (30 ml water) leads to 90% debromination of 1 g HIPS-Br but plastic is strongly degraded and could not be recovered. previous termAlkalinenext term hydrothermal treatment (45 ml or 60 ml KOH 1 M) showed similar debromination for up to 12 g HIPS-Br and plastic was recovered as pellets with molecular weight distribution close to that of the initial material. Debromination occurs at melt plastic/KOH solution interface when liquid/vapour equilibrium is attained inside autoclave (280℃ and 7 MPa in our experimental conditions) and depends on the plastic amount/KOH volume ratio. The antimony oxide synergist from HIPS-Br remains in recovered plastic during treatment. A pictorial imagination of the proposed debromination process is presented.</p>No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0968-089615192007Antitumor studies. Part 3: Design, synthesis, antitumor activity, and molecular docking study of novel 2-methylthio-, 2-amino-, and 2-(N-substituted amino)-10-alkyl-2-deoxo-5-deazaflavins63366352ENHamed I.AliNoriyukiAshidaTomohisaNagamatsuVarious novel 10-alkyl-2-deoxo-2-methylthio-5-deazaflavins have been synthesized by reaction of 6-(N-alkylanilino)-2-methylthiopyrimidin-4(3H)-ones with Vilsmeier reagent. The similar 2-(N-substituted amino) derivatives were prepared by nucleophilic replacement reaction of the 2-methylthio moiety by appropriate amines. The 2-oxo derivatives (i.e., 5-deazaflavins) were obtained by acidic hydrolysis of the 2-methylthio derivatives. The antitumor activities against CCRF-HSB-2 and KB cells and the antiviral activities against HSV-1 and HSV-2 have been investigated in vitro, and many compounds showed promising antitumor activities. Furthermore, AutoDock molecular docking into PTK has been done for lead optimization of these compounds as potential PTK inhibitors. Whereas, the designed 2-deoxo-5-deazaflavins connected with amino acids at the 2-position exhibited the good binding affinities into PTK with more hydrogen bonds.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0968-08961512007Antitumor studies. Part 1: Design, synthesis, antitumor activity, and AutoDock study of 2-deoxo-2-phenyl-5-deazaflavins and 2-deoxo-2-phenylflavin-5-oxides as a new class of antitumor agents242256ENHamed I..AliKeiichiroTomitaEiichiAkahoHirotoKambaraShinjiMiuraHiroyukiHayakawaNoriyukiAshidaYutakaKawashimaTakehiroYamagishiHisaoIkeyaFumioYonedaTomohisaNagamatsuNovel 2-deoxo-2-phenyl-5-deazaflavins and 2-deoxo-2-phenylflavin-5-oxides were prepared as a new class of antitumor agents and showed significant antitumor activities against NCI-H 460, HCT 116, A 431, CCRF-HSB-2, and KB cell lines. In vivo investigation, 2-deoxo-10-methyl-2-phenyl-5-deazaflavin exhibited the effective antitumor activity against A 431 human adenocarcinoma cells transplanted subcutaneously into nude mouse. Furthermore, AutoDock study has been done by binding of the flavin analogs into PTK pp60(c-src), where a good correlation between their IC50 and AutoDock binding free energy was exhibited. In particular, 2-deoxo-2-phenylflavin-5-oxides exhibited the highest potential binding affinity within the binding pocket of PTK.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0968-08961622008Antitumor studies. Part 4: Design, synthesis, antitumor activity, and molecular docking study of novel 2-substituted 2-deoxoflavin-5-oxides, 2-deoxoalloxazine-5-oxides, and their 5-deaza analogs922940ENHamed I.AliNoriyukiAshidaTomohisaNagamatsuVarious novel 10-alkyl-2-deoxo-2-methylthioflavin-5-oxides and their 2-alkylamino derivatives were prepared by facile nitrosative cyclization of 6-(N-alkylanilino)-2-methylthiopyrimidin-4(3H)-ones followed by nucleophilic replacement of the 2-methylthio moiety by different amines, and acidic hydrolysis of the 2-methylthio moiety afforded the corresponding flavin derivatives. 2-Deoxo-2-methylthio-5-deazaalloxazines and 2-deoxo-2-methylthioalloxazine-5-oxides were also prepared by Vilsmeier reaction and by nitrosation of 6-anilino-2-methylthiopyrimidin-4(3H)-ones, respectively. Then, they were subjected to nucleophilic replacement with appropriate amines to produce the corresponding 2-alkylamino derivatives. Regiospecific N-3-alkylation of 2-deoxo-2-methylthioalloxazine-5-oxides was carried out with various alkylating agents in the usual way, The antitumor activities against CCRF-HSB-2 and KB tumor cells have been investigated in vitro, and many compounds showed promising antitumor activities. Furthermore, AutoDock molecular docking into PTK (PDB: 1t46) has been done for lead optimization of the aforementioned compounds as potential PTK inhibitors.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0040-40206492008Efficient total syntheses of natural pterin glycosides: limipterin and tepidopterin20902100ENTadashiHanayaHirokiBabaHirokiToyotaHiroshiYamamotoThe key, versatile precursors N-2-(N,N-dimethylaminomethylene)-1'-O-(4-methoxybenzyl)-3-[2-(4-nitrophenyl)ethyl]biopterin (29a) and its ciliapterin analog (29b) were prepared, respectively, from D-xylose (in 14 steps) and L-xylose (in 11 steps). Treatment of 29a and 29b with 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-beta-D-glucopyranosyl bromide in the presence of silver triflate and tetramethylurea, followed by removal of the protecting groups, led to the first selective syntheses of limipterin (3) and tepidopterin (5), respectively.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0040-402065382009Synthetic studies on pterin glycosides: the first synthesis of 2′-O-(α-d-glucopyranosyl)biopterin79897997ENTadashiHanayaHirokiBabaHirokiToyotaHiroshiYamamotoL-Rhamnose was led, in a 14-step-sequence, to N2-(N,N-dimethylaminomethylene)-1′-O-(4-methoxybenzyl)-3-[2-(4-nitrophenyl)ethyl]biopterin (23), an appropriately protected precursor for 2′-O-glycosylation, while 4,6-di-O-acetyl-2,3-di-O-(4-methoxybenzyl)-α-d-glucopyranosyl bromide (32), a novel glycosyl donor, was efficiently prepared from d-glucose in 8 steps. The first synthesis of 2′-O-(α-d-glucopyranosyl)biopterin (2a) was achieved by treatment of the key intermediate 23 with 32 in the presence of silver triflate and tetramethylurea, followed by successive removal of the protecting groups.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0003-99695682011Effects of exercise training on gingival oxidative stress in obese rats768774ENTetsujiAzumaTakaakiTomofujiYasumasaEndoNaofumiTamakiDaisukeEkuniKoichiroIrieKentaKasuyamaTomoKatoManabuMoritaObjective: The purpose of the present study was to investigate the effects of exercise training on serum reactive oxygen species (ROS) level and gingival oxidative stress in obese rats fed a high-fat diet. Design: Rats were divided into three groups (n = 14/group): one control group (fed a regular diet) and two experimental groups (fed a high-fat diet with and without exercise training [treadmill: 5 days/week]). The rats were sacrificed at 4 or 8 weeks. The level of serum reactive oxidative metabolites (ROM) was measured as an indicator of circulating ROS. The level of 8-hydroxydeoxyguanosine (8-OHdG) and reduced-form glutathione (GSH)/oxidised-form glutathione (GSSG) ratio were determined to evaluate gingival oxidative stress. Results: The obese rats fed a high-fat diet without exercise training showed higher serum ROM levels [Carratelli Units (CARR U)] (mean +/- SD; 413 +/- 64) than the control (333 +/- 12) at 4 weeks (p = 0.023). Such a condition resulted in higher 8-OHdG levels (ng/mg mtDNA) (0.97 +/- 0.18) (p < 0.05) and a lower GSH/GSSG ratio (17.0 +/- 3.1) (p < 0.05) in gingival tissues, compared to the control (0.55 +/- 0.13 for 8-OHdG and 23.6 +/- 5.8 for GSH/GSSG ratio) at 8 weeks. In addition, the obese rats fed a high-fat diet with exercise training showed lower serum ROM (623 +/- 103) (p<0.001) and gingival 8-OHdG levels (0.69 +/- 0.17) (p = 0.012) than those without exercise training (1105 95 for ROM and 0.55 +/- 0.13 for 8-OHdG) at 8 weeks. Conclusions: Obesity prevention by exercise training may effectively suppress gingival oxidative stress by decreasing serum ROS in rats.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama1357-27254212010Scleraxis and E47 cooperatively regulate the Sox9-dependent transcription148156ENTakayukiFurumatsuChisaShukunamiMichiyoAmemiya-KudoHitoshiShimanoToshifumiOzakiDuring musculoskeletal development, Sry-type HMG box 9 (Sox9) has a crucial role in mesenchymal condensation and chondrogenesis. On the other hand, a tissue-specific basic helix-loop-helix (bHLH) transcription factor Scleraxis (Scx) regulates the differentiation of tendon and ligament progenitors. Whereas these two transcription factors cooperatively participate in the determination of cellular lineages, the precise interaction between Sox9 and Scx remains unclear. We have previously demonstrated that the Sox9-dependent transcription is synergistically activated by several Sox9-associating molecules, such as p300 and Smad3, on chromatin. In this study, we investigated the function of Scx in the Sox9-dependent transcription. The expression of α1(II) collagen (Col2a1) gene was stimulated by an appropriate transduction of Sox9 and Scx. Scx and its partner E47, which dimerizes with other bHLH proteins, cooperatively enhanced the Sox9-dependent transcription in luciferase reporter assays. Coactivator p300 synergistically increased the activity of Sox9-regulated reporter gene, which contains promoter and enhancer regions of Col2a1, in the presence of Scx and E47. Immunoprecipitation analyses revealed that Scx and E47 formed a transcriptional complex with Sox9 and p300. Scx/E47 heterodimer also associated with a conserved E-box sequence (CAGGTG) in the Col2a1 promoter on chromatin. These findings suggest that Scx and E47 might modulate the primary chondrogenesis by associating with the Sox9-related transcriptional complex, and by binding to the conserved E-box on Col2a1 promoter.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama1357-27254152009Smad3 activates the Sox9-dependent transcription on chromatin11981204ENTakayukiFurumatsuToshifumiOzakiHiroshiAsaharaTransforming growth factor (TGF)-β has an essential role for the Sry-type high-mobility-group box (Sox)-regulated chondrogenesis. Chondrogenic differentiation is also controlled by chromatin-mediated transcription. We have previously reported that TGF-β-regulated Smad3 induces chondrogenesis through the activation of Sox9-dependent transcription. However, the cross-talk between TGF-β signal and Sox9 on chromatin-mediated transcription has not been elucidated. In the present study, we investigated the activity of Smad3, Sox9, and coactivator p300 using an in vitro chromatin assembly model. Luciferase reporter assays revealed that Smad3 stimulated the Sox9-mediated transcription in a TGF-β-dependent manner. Recombinant Sox9 associated with phosphorylated Smad3/4 and recognized the enhancer region of type II collagen gene. In vitro transcription and S1 nuclease assays showed that Smad3 and p300 cooperatively activated the Sox9-dependent transcription on chromatin template. The combination treatment of phosphorylated Smad3, Sox9, and p300 were necessary for the activation of chromatin-mediated transcription. These findings suggest that TGF-β signal Smad3 plays a key role for chromatin remodeling to induce chondrogenesis via its association with Sox9.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0003-99695612011Occlusal disharmony induces BDNF level in rat submandibular gland3540ENKoichiroIrieDaisukeEkuniTakaakiTomofujiTetsujiAzumaYasumasaEndoKentaKasuyamaManabuMoritaObjectives: Brain-derived neurotrophic factor (BDNF), which is produced in rat submandibular gland, is one of the most abundant neurotrophins in the central nervous system. It is generally accepted that occlusal disharmony causes stress. The purpose of the present study was to investigate whether occlusal disharmony-induced chronic stress affects BDNF levels and morphology in rat submandibular gland. Design: Eight wks old male Wistar rats (n = 21) were randomly divided into three groups of 7 rats. In a control (C) group, the rats received no treatment for 8 wks. In a molar cusp-less (OD) group, maxillary molar cusps were cut off with a dental turbine at baseline and kept for 8 wks. In a molar cusp-less + recovered cusp (OR) group, maxillary molar cusps were cut off and then were recovered after 4 wks using resin material. After the experimental period, expression of BDNF mRNA and protein as well as histological findings were evaluated in the submandibular glands. The comparisons between the groups were made using the Mann-Whitney U test with Bonferroni correction. Results: The OD group showed a significant increase in submandibular gland BDNF mRNA and protein expression after 8 wks, and plasma adrenocorticotropic hormone and corticosterone levels increased in a time-dependent manner. There were no significant differences in BDNF expression in the submandibular glands and in levels of plasma adrenocorticotropic hormone and corticosterone between the OR and C groups. Conclusions: These results indicate that psychological stress induced by occlusal disharmony reversibly induces BDNF expression in the rat submandibular gland.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0960-894X20202010Quantitative screening of EGF receptor-binding peptides by using a peptide library with multiple fluorescent amino acids as fluorescent tags59765978ENMizukiKitamatsuTakahiroYamamotoMidoriFutamiMasahikoSisidoEGF receptor-binding peptides could be found by a peptide screening method using fifteen fluorescent amino acids as fluorescent tags. Of 225 peptides, we found an 8-mer peptide containing a dipeptide unit, Y-F, which was the strongest binding peptide to the EGF receptor.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0040-402066512010Synthesis of pyrrolidine-based oxy-peptide nucleic acids carrying four types of nucleobases and their transport into cytoplasm96599666ENMizukiKitamatsuAkikoTakahashiTakashiOhtsukiMasahikoSisidoWe synthesized 16 pyrrolidine-based oxy-peptide nucleic acid (POPNA) monomers carrying four different nucleobases onto four different stereoisomers of pyrrolidine rings. Using these monomers, we prepared POPNA oligomers, which formed sequence-specific hybrids with DNAs. The oligomer configurations influenced the hybrid stability. The oligomers were not taken into CHO cells. However, they could enter the cell cytoplasm when mixed with the influenza virus hemagglutinin peptide-arginine heptamer conjugate.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0960-894X21192011In vivo anti-inflammatory and antioxidant properties of ellagitannin metabolite urolithin A59015904ENHidekazuIshimotoMariShibataYukiMyojinHideyukiItoYukioSugimotoAkihiroTaiTsutomuHatanoUrolithin A is a major metabolite produced by rats and humans after consumption of pomegranate juice or pure ellagitannin geraniin. In this study, we investigated the anti-inflammatory effect of urolithin A on carrageenan-induced paw edema in mice. The volume of paw edema was reduced at 1 h after oral administration of urolithin A. In addition, plasma in treated mice exhibited significant oxygen radical antioxidant capacity (ORAC) scores with high plasma levels of the unconjugated form at 1 h after oral administration of urolithin A. These results indicate strong associations among plasma urolithin A levels, the plasma ORAC scores, and anti-inflammatory effects and may help explain a mechanism by which ellagitannins confer protection against inflammatory diseases.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0008-622349102011Superhydrophilicity on nano-rough carbon surfaces achieved by hyperthermal oxygen-atom beam exposure33883391ENHiroshiKinoshitaTakashiNakayamaNaohiroMatsumotoNobuoOhmaeIn order to investigate a method to increase hydrophilicity on nano-rough carbon surfaces, a nano-rough surface of C(60) film and an atomically flat surface of highly oriented pyrolytic graphite (HOPG) were oxidized by hyperthermal oxygen-atom beam exposure and the hydrophilicities of the surfaces were investigated. Superhydrophilicity were achieved on these exposed carbon surfaces, which had low O/C ratio of approximately 28% and surface roughness (Ra) of approximately 3 nm. The direct oxidations on sp(2) bonded carbon atoms (basal plane) of these two carbon materials by the exposure of hyperthermal O-atom beam would contribute the superhydrophilicity.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0160-41203752011Long-term exposure to methylmercury and psychiatric symptoms in residents of Minamata, Japan907913ENTakashiYorifujiToshihideTsudaSachikoInoueSoshiTakaoMasazumiHaradaIntroduction: It is well-known that prenatal or postnatal exposure to methylmercury can produce neurological signs in adults and children, exemplified by a case of large-scale poisoning in Minamata, Japan, in the 1950s. However, evidence regarding whether pre- or postnatal exposure to methylmercury causes psychiatric symptoms (e.g., impairment of intelligence and mood and behavioral dysfunction) is still limited-excluding cases of fetal Minamata disease patients. Methods: We evaluated the effects of pre- or postnatal exposure to methylmercury on psychiatric symptoms using data derived from a 1971 population-based survey in Minamata and neighboring communities. We adopted residential areas as an exposure indicator and psychiatric symptoms as the outcome. Then, we estimated the adjusted prevalence odds ratio (POR) and confidence interval (Cl) of psychiatric symptoms in relation to residential area. Results: There were 904 participants in Minamata (high exposure area), 1700 in Goshonoura (middle exposure area), and 913 in Ariake (low exposure area). Compared to the Ariake area, participants in the Minamata area manifested psychiatric symptoms more frequently: PORs for impairment of intelligence and mood and behavioral dysfunction were 5.2 (95% Cl: 3.7-7.3) and 4.4 (95% Cl: 2.9-6.7), respectively. Furthermore, participants with psychiatric symptoms in the Minamata area more frequently had neurological signs. Peaks in prevalence of psychiatric symptoms occurred around age 20 and in older age adults in the area. These findings did not change when we excluded those who had been officially certified as Minamata disease patients by that time. Conclusions: The present study suggests a relationship between pre- or postnatal exposure to methylmercury and psychiatric symptoms among the general population in Minamata even after excluding officially certified patients.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0040-40395122010Palladium- and base-free synthesis of conjugated ynones by cross-coupling reactions of alkynylboronates with acid chlorides mediated by CuCl306308ENYasushiNishiharaDaisukeSaitoEijiInoueYoshiakiOkadaMikihiroMiyazakiYoshiakiInoueKentaroTakagiAlkynylboronates can be employed as a practical and versatile precursor for a variety of pi-conjugated organic compounds. In the presence of Cu(I) salt, cross-coupling reactions of acid chlorides with alkynylboronates giving rise to the corresponding conjugated ynones takes place readily in aprotic polar solvents such as DMI under neutral conditions.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0003-99695922014Memory-related gene expression profile of the male rat hippocampus induced by teeth extraction and occlusal support recovery133141ENSachiyoIidaTetsuyaHaraDaisukeArakiChisaIshimine-KurodaAkimasaKurozumiShunichiSakamotoTakakoMiyazakiShogoMinagiObjectives: The present study aimed to identify the effect of memory-related genes on male rats tested for spatial memory with either molar teeth extraction or its restoration by occlusal support using experimental dentures.
Design: Memory-related genes were detected from hippocampi of male Wistar rats (exposed to teeth extraction with or without dentures, or no extraction (control)) (7-week old) after behavioural testing (via the radial maze task) using a DNA microarray. The time course of the expression of these genes was evaluated by quantitative real-time polymerase chain reaction (PCR) (on 49-week-old rats).
Results: In preliminary experiments, to determine which memory genes are affected by spatial memory training, DNA microarray analysis revealed that thyrotropin-releasing hormone (Trh) and tenascin XA (Tnxa) were up-regulated and neuronatin (Nnat) and S100a9 were down-regulated after the maze training. The expression of Tnxa, Nnat and S100a9 of 49-week-old rats (during the time course) via quantitative real-time PCR was consistent with the results of microarrays of the preliminary experiment. Expression of Trh that was evaluated by quantitative real-time PCR did not agree with the results for this gene from the microarray for all groups. Therefore, expression of Trh may have increased in only young, trained rats. The expression of S100a9 prior to the maze task was down-regulated in only the extraction group.
Conclusion: These results demonstrated that Trh, Tnxa and Nnat genes were affected according to the degree of memory in male rats. This study also indicated that S100a9 is a memory-related gene, which is affected by the presence of occlusal support.No potential conflict of interest relevant to this article was reported.Pergamon-Elsevier Science Ltd.Acta Medica Okayama0003-996959122014Assessment of intraoral mucosal pain induced by the application of capsaicin13341341ENRyujiTerayamaKotaroMaruhamaHirokiTsuchiyaMasahideMizutaniSeijiIidaTomosadaSugimotoObjective
To develop an objective method for assessing nociceptive behaviour in an animal model of capsaicin-induced intraoral pain. Changes in nociceptive responses were also examined after injury to the inferior alveolar nerve (IAN).
Design
Nociceptive responses evoked by the intraoral application of various doses of capsaicin were analyzed in lightly anaesthetized rats. The number of c-Fos protein-like immunoreactive (Fos-LI) neurons in the medullary dorsal horn (MDH) induced by the intraoral application of capsaicin was measured. Behavioural and c-Fos responses were also examined 14 days after injury to the IAN.
Results
Larger doses of intraoral capsaicin (1, 10 and 100 μg) induced vigorous licking behaviour and c-Fos response in the MDH in a reproducible manner. The magnitudes of both behavioural activity and the c-Fos response from the 10 and 100 μg doses of capsaicin were significantly greater than that by the 1 μg dose. Injury to the IAN exaggerated the behavioural and c-Fos responses evoked by intraoral capsaicin.
Conclusions
The intraoral application of capsaicin is a valid and reliable method for studying intraoral pain and hyperalgesia following nerve injury.No potential conflict of interest relevant to this article was reported.