Analgesic Effects of Toad Cake and Toad-cake-containing Herbal Drugs

Objectives: This study was conducted to clarify the analgesic effect of toad cake and toad-cake-containing herbal drugs. Methods: We counted the writhing response of mice after the intraperitoneal administration of acetic acid as a nociceptive pain model and the withdrawal response after the plantar surface stimulation of the hind paw induced by partial sciatic nerve ligation of the mice as a neuropathic pain model to investigate the analgesic effect of toad cake and toad-cake-containing herbal drugs. A co-treatment study with serotonin biosynthesis inhibitory drug 4-chloro-DL-phenylalanine methyl ester hydrochloride (PCPA), the catecholamine biosynthesis inhibitory drug α-methyl-DL-tyrosine methyl ester hydrochloride (AMPT) or the opioid receptor antagonist naloxone hydrochloride was also conducted. Results: Analgesic effects in a mouse model of nociceptive pain and neuropathic pain were shown by oral administration of toad cake and toad-cake-containing herbal drugs. The effects of toad cake and toad-cake-containing herbal drugs disappeared upon co-treatment with PCPA, but not with AMPT or naloxone in the nociceptive pain model; the analgesic effect of toad-cake-containing herbal drugs also disappeared upon co-treatment with PCPA in the neuropathic pain model. Conclusion: Toad cake and toad-cake-containing herbal drugs have potential for the treatments of nociceptive pain and of neuropathic pain, such as post-herpetic neuralgia, trigeminal neuralgia, diabetic neuralgia, and postoperative or posttraumatic pain, by activation of the central serotonin nervous system

Dynamical Structure of Nano-Meter-Sized Domains on a Vesicle(Poster session 1, New Frontiers in Colloidal Physics : A Bridge between Micro- and Macroscopic Concepts in Soft Matter)

この論文は国立情報学研究所の電子図書館事業により電子化されました。飽和リン脂質、不飽和リン脂質、コレステロールの3成分からなるモデル生体膜は、脂質アシル基の無秩序-秩序転移温度以下で相分離し、膜面上にドメイン構造を形成する。ナノメートルサイズのベシクルを用いることにより膜面上でのナノメートルスケールのドメインのダイナミクスを中性子スピンエコー法により調べた。臨界サイズに近い大きさを持つナノドメインはベシクル上で熱揺らぎにより融合・分裂を繰り返し、安定なモノドメイン構造にまで成長できない状態であると考えられる

First Experiment of Spin Contrast Variation Small-Angle Neutron Scattering on the iMATERIA Instrument at J-PARC

Recently, we have developed a novel dynamic nuclear polarization (DNP) apparatus with a magnetic field of 7 T and a sample temperature of 1 K. High proton spin polarizations from −84% to 76%, for TEMPO doped polystyrene samples, have been demonstrated. This DNP apparatus satisfies the simultaneous requirement for quick and easy sample exchange and high DNP performance. On the iMATERIA (BL20) instrument at J-PARC, the first beam experiment using this DNP apparatus has been performed. For this experiment, the beamline was equipped with a supermirror polarizer. The stray magnetic field due to the superconducting magnet for DNP was also evaluated. The stray magnetic field plays an important role for in maintaining the neutron polarization during the transportation from the polarizer to the sample. The small-angle neutron scattering (SANS) profiles of silica-filled rubber under dynamically polarized conditions are presented. By applying our new analytical approach for SANS coherent scattering intensity, neutron polarization (PN) as a function of neutron wavelength was determined. Consequently, for the neutron wavelength, range from 4 Å to 10 Å, |PN| was sufficient for DNP-SANS studies

Agarwood Inhibits Histamine Release from Rat Mast Cells and Reduces Scratching Behavior in Mice Effect of Agarwood on Histamine Release and Scratching Behavior

Objectives: This study was conducted to clarify the effects of agarwood on histamine release from mast cells in rats and on the scratching behaviors in mice. Methods: Histamine release from rat mast cells induced by compound 48/80 or concanavalin A (Con A) and compound 48/80-induced scratching behavior in mice were examined to investigat

In Situ Observation on Hierarchical Actin Bundle Networks(Poster session 1, New Frontiers in Colloidal Physics : A Bridge between Micro- and Macroscopic Concepts in Soft Matter)

この論文は国立情報学研究所の電子図書館事業により電子化されました。アメーバ運動は、生体内の細胞骨格タンパク質であるアクチンがアクチン結合タンパク質を介して形成するバンドル、二次元ネットワーク、三次元ゲル構造の構築と消滅の制御によって生み出されている。本研究では、アクチン結合タンパク質のモデルとしてポリカチオンを用い、フィラメントアクチンとポリカチオンが形成する複合体構造を中性子超小角散乱法を用いて観察した。その結果、ポリカチオン濃度の増大によるバンドル内のフィラメント密度の増大、および、塩濃度の増加によるバンドル構造の消滅を明らかにした。Actin is one of the most abundant cytoskeleton proteins in eucaryotic cell. They play a crucial role in cell motility by polymerizing monomeric globular G-actin into polymeric filamentous actin (F-actin). With actin-binding proteins (ABPs), they form higher order structures such as linear bundles, two-dimensional networks and three-dimensional gels. It has been considered that these structures are controlled by ABPs. However recent study have shown that the only one kind of artificial cationic polymer can form variety of structures depending its concentration and salt concentration. This system is a good model to elucidate the mechanism of regulation of actin and ABPs complex structure. Based on these backgrounds, we have investigated the effects of salt concentration on the stability and structure of actin-polycation complexes by using small angle neutron scattering (SANS) technique

Deuterated Glutamate-Mediated Neuronal Activity on Micro-Electrode Arrays

The excitatory synaptic transmission is mediated by glutamate (GLU) in neuronal networks of the mammalian brain. In addition to the synaptic GLU, extra-synaptic GLU is known to modulate the neuronal activity. In neuronal networks, GLU uptake is an important role of neurons and glial cells for lowering the concentration of extracellular GLU and to avoid the excitotoxicity. Monitoring the spatial distribution of intracellular GLU is important to study the uptake of GLU, but the approach has been hampered by the absence of appropriate GLU analogs that report the localization of GLU. Deuterium-labeled glutamate (GLU-D) is a promising tracer for monitoring the intracellular concentration of glutamate, but physiological properties of GLU-D have not been studied. Here we study the effects of extracellular GLU-D for the neuronal activity by using primary cultured rat hippocampal neurons that form neuronal networks on microelectrode array. The frequency of firing in the spontaneous activity of neurons increased with the increasing concentration of extracellular GLU-D. The frequency of synchronized burst activity in neurons increased similarly as we observed in the spontaneous activity. These changes of the neuronal activity with extracellular GLU-D were suppressed by antagonists of glutamate receptors. These results suggest that GLU-D can be used as an analog of GLU with equivalent effects for facilitating the neuronal activity. We anticipate GLU-D developing as a promising analog of GLU for studying the dynamics of glutamate during neuronal activity

Structure and Mechanical Properties of Polybutadiene Thin Films Bound to Surface-Modified Carbon Interface

The structure and mechanical properties of polybutadiene (PB) films on bare and surface-modified carbon films were examined. There was an interfacial layer of PB near the carbon layer whose density was higher (lower) than that of the bulk material on the hydrophobic (hydrophilic) carbon surface. To glean information about the structure and mechanical properties of PB at the carbon interface, a residual layer (RL) adhering to the carbon surface, which was considered to be a model of “bound rubber layer”, was obtained by rinsing the PB film with toluene. The density and thickness of the RLs were identical to those of the interfacial layer of the PB film. In accordance with the change in the density, normal stress of the RLs evaluated by atomic force microscopy was also dependent on the surface free energy: the RLs on the hydrophobic carbon were hard like glass, whereas those on the hydrophilic carbon were soft like rubber. Similarly, the wear test revealed that the RLs on the hydrophilic carbon could be peeled off by scratching under a certain stress, whereas the RLs on the hydrophobic carbons were resistant to scratching