Inflammatory cytokines in degeneration, regeneration and maintenance of sciatic nerve

Inflammatory cytokines play important roles in a variety of pathophysiological changes associated with traumatic injury and demyelinating disorders in the peripheral nervous system. After sciatic nerve injury, proinflammatory cytokines such as interleukin 1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNFα) are produced by and act on neurons, Schwann cells, and infiltrating inflammatory cells at the lesion site. Underlying these processes is receptor-mediated activation of intracellular signaling pathways that regulate cell differentiation and proliferation and synthesis of axon and myelin components. This review focuses on roles of inflammatory cytokines in the degeneration and regeneration of the peripheral nerve. In addition, we describe here altered expression of inflammatory cytokines in gradually elongated rat sciatic nerves. This experimental model, which is devoid of Wallerian degeneration, provides insights into the involvement of inflammatory cytokines in the maintenance of myelinated axons. Based on the findings obtained from nerve elongation models and those from conventional nerve injury models, we discuss the molecular mechanism that ensures the integrity of the peripheral nerve. © 2011 by Nova Science Publishers, Inc. All rights reserved

A critical role of holistic processing in face gender perception

Whether face gender perception is processed by encoding holistic (whole) or featural (parts) information is a controversial issue. Although neuroimaging studies have identified brain regions related to face gender perception, the temporal dynamics of this process remain under debate. Here, we identified the mechanism and temporal dynamics of face gender perception. We used stereoscopic depth manipulation to create two conditions: the front and behind condition. In the front condition, facial patches were presented stereoscopically in front of the occluder and participants perceived them as disjoint parts (featural cues). In the behind condition, facial patches were presented stereoscopically behind the occluder and were amodally completed and unified in a coherent face (holistic cues). We performed three behavioral experiments and one electroencephalography experiment, and compared the results of the front and behind conditions. We found faster RT in the behind condition compared with the front, and observed priming effects and aftereffects only in the behind condition. Moreover, the EEG experiment revealed that face gender perception is processed in the relatively late phase of visual recognition (200-285 ms). Our results indicate that holistic information is critical for face gender perception, and that this process occurs with a relatively late latency

膜電位依存性K^+チャンネルの分子生物学的解析

金沢大学医学部研究課題/領域番号:03857031, 研究期間(年度):1991出典：研究課題「膜電位依存性K^+チャンネルの分子生物学的解析」課題番号03857031（KAKEN：科学研究費助成事業データベース（国立情報学研究所）） （https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-03857031/）を加工して作

電位依存性ナトリウム・カリウムチャネルの神経障害性疼痛に伴う発現異常の分子機構

研究経過・結果は以下の通りである。1.ラット膜電位依存性カリウムチャネルの構成サブユニット(Kv1.1とKv1.2)のアミノ酸配列にもとずく合成ペプチドをウサギに免疫し、抗血清を抗原ペプチド結合カラムクロマトグラフィーによって精製した。2.上記抗体を用いてKv1.1あるいはKv1.2の相補DNAを導入したCOS-7細胞で特異的な免疫染色が認められた。いずれの抗体でも、ラット小脳膜分画を用いたウエスタンブロット解析において、特異的なバンドを検出された。3.ラット腰部脊髄後根神経節と三叉神経節を酵素抗体法によって染色したところ、Kv1.1あるいはKv1.2の免疫反応性は中型から大型の神経細胞体で観察された。これらの細胞体の50%以上はニューロフィラメント(RT97)陽性であった。ペリフェリンと同時陽性の細胞は僅かであった。4.脊髄後角では、Kv1.1、Kv1.2の免疫反応性は深部III-IV層で顕著であった。5.ヒラメ筋では、Kv1.1およびKv1.2の免疫反応性が螺旋状の構造物に認められ、抗ニューロフィラメント抗体にも反応性を示したことから感覚ニューロンの末梢側受容体であることが示唆された。6.下肢皮下への蛍光標識金コロイド注入後に標識されるL4後根神経節内の細胞体の一部はKv1.1あるいはKv1.2陽性であり、皮膚感覚ニューロンの少なくとも一部にこれらのチャネルが発現していることが示された。7.坐骨神経切断後の腰部脊髄後根神経節でKv1.1およびKv1.2の免疫反応性の低下が認められた。したがって、生理的状態でKv.1.1、Kv1.2チャネルは筋および皮膚に分布する非侵害性感覚受容ニューロンにおける活動電位の大きさ、頻度、伝播等を調節していると示唆された。同時に、これらのチャネルの発現低下は神経損傷後の痛覚過敏、アロディニアの一因となる可能性が推測された。Kv1.1 and Kv1.2, two most closely related members of the Shaker-like gene subfamily, encode pore-forming subuaits of voltage-gated potassium (K^+) channels. To clarify physiological roles of these proteins in primary sensory afferentiation, we have performed inimunohistochemical analysis using specific antidodies. Immunoperoxidase staining of dorsal root and trigeminal ganglia revealed that strong immunoreactivity (IR) for Kv1.1 and Kv1.2 was predominant in medium- and large-sized neurons. In double-immunofluorescence experiments, the cells strongly positive for these subunits were most frequently observed in RT97 (neurofilament)-positive large neurons; but rarely in peripherin- or IB4-positive small neurons. In the spinal dorsal horn, both the aati-Kv1.1 and anti-Kv1.2 antibodies heavily staiaed the deeper laminae III-IV. At the electron microscopic level, IRs for these proteins were preferentially localized in myelinated axons with large diameter. These results suggest that voltage-gated K^+ channels composed of Kv 1.1 and/or Kv 1.2 subunits may play important roles in conducting mechanoceptive and proprioceptiye sensation from skin and muscles. Conceivably, decreased expression of these channels after injury might cause hypereexcitability of neurons, thereby leading to hyperalgegia or allodyaia.研究課題/領域番号:11680753, 研究期間(年度):1999-2002出典：「電位依存性ナトリウム・カリウムチャネルの神経障害性疼痛に伴う発現異常の分子機構」研究成果報告書　課題番号11680753 (KAKEN：科学研究費助成事業データベース（国立情報学研究所）)　　　本文データは著者版報告書より作

一次求心性Aβ線維のイオンチャネル発現異常が神経障害性疼痛発生に与える影響

抗カリウムチャネル(Kv1.1、Kv1.2)抗体を作製し、末梢神経系での局在を調べた。その結果、これらのチャネルはk筋および皮膚に分布する非侵害性感覚受容ニューロンに優位に発現していた。また、神経損傷後にKv1.2チャネルの発現低下が見られた。これらの結果から、Kv1.2チャネルの神経損傷時の発現低下が、非痛覚(触覚、振動覚、温度覚等)ニューロンと二次痛覚ニューロンとの異所性シナプスの形成と相侯って、痛覚過敏、アロディニアで観察されるような過剰膜興奮を来たす可能性が示唆された。末梢神経の損傷および損傷前段階で誘導される因子を同定するために、成体ラットの坐骨神経を延長した。伸長速度が1.0、2.0、20.0mm/日の3群に分け、いずれも合計20.0mmまで伸長した。腰部脊髄後根神経節および坐骨神経からRNAを抽出し、インターロイキン1β(IL1β)、インターロイキン6(IL6)、腫瘍壊死因子α(TNFα)、神経成長因子(NGF)、脳由来神経栄養因子(BDNF)、ニューロトロフィン3(NT-3)、ニューロトロフィン4/5(NT-4/5)のmRNAの発現量をRT-PCRによって調べた。腰部脊髄後根神経節では、IL6のmRNA量が顕著に上昇し、TNFα、NGF、BDNF、NT-3、NT-4/5のmRNA量に変化は認められなかった。また、坐骨神経では、TNFαのmRNA量が上昇し、IL1β、IL6、NGF、BDNF、NT-3、NT-4/5のmRNA量に変化は認められなかった。これらの発現上昇は、Waller変性が認められない1.0、2.0mm/日群でも有意であった。IL6、TNFαは、神経損傷時にニューロン、シュワン細胞で誘導される主要な因子であると想定された。今後、IL6およびTNFαが膜電位依存性チャネル(特にKv1.1とKv1.2)の発現量を変化させるかどうか調べる予定である。Kvl.1 and Kv1.2 are closely related pore-forming subunits of voltage-gated potassium (K+) channels, and are abundantly expressed in the peripheral nervous system. To clarify biological roles of these subunits in primary sensory afferentiation, we performed immunohistochemical analysis using specific polyclonal antidodies. In immunopeoxidase staining, dorsal root and trigeminal ganglia revealed that intense immunoreactivity (IR) for Kvl.1 and Kv1.2 was prediominant in medium to large cell bodies of primary sensory neurons. Double-immunofluorescence experiments revealed that the strongly immunoreactive neurons were most frequently RT97 (neurofilament)-positive; but rarely peripherin-or IB4-positive. In the spinad dorsal horn, both the anti-Kvl.1 and anti-Kv1.2 antibodies heavily stained the deeper laminae III-IV. These results suggest that voltage-gated channels composed of Kvl.1 and/or Kv1.2 subunits may play important roles in conducting mechanoceptive and proprioceptive sensation from skin and muscles. We also observed that, when sciatic nerve was ligated, Kv1.2-IR was reduced in DRG neurons. We now hypothesize that activities of particular subtypes of K+ channels are reduced after peripheral nerve injury, resulting in abnormal excitability of primary sensory neurons, (manuscript, in preparation) In pararell, we attempted to identify proteins unregulated after peripheral nerve perturbation. We demonstrated that sciatic nerve elongation induces production of interleukin-6 (IL-6) in DRG neurons and tumor necrosis factor-alpha (TNF-α) in Schwann cells. The induction was detected not only in the acutely elongated 20-mm/d group, in which nuclear eccentricity in the cell body and degenerated axons were observed, but also in the gradually elongated 1-and 2-mm/d groups, in which no degenerative change was detectable. These data indicate that the expression levels of IL-6 and TNF-α are regulated delicately in the peripheral nervous system. (Osamura, et al., Exp. Neurol. 191: 61-70, 2005; Hagiwara et al., J. Orthop. Sci.10: 614-621, 2005) In the future, we will examine whether or not IL-6 and TNF-α alter expression levels of Kvl.1 and Kv1.2 proteins in neuropathic pain models.研究課題/領域番号:15500255, 研究期間(年度):2003-2005出典：「一次求心性Aβ線維のイオンチャネル発現異常が神経障害性疼痛発生に与える影響」研究成果報告書　課題番号15500255 (KAKEN：科学研究費助成事業データベース（国立情報学研究所）)　　　本文データは著者版報告書より作

膜電位依存性K^+チャネル(KV3.1)に会合する調節蛋白のcDNAクローニング

金沢大学医薬保健研究域医学系1. カリウム(K+)チャネル(Kv3.la)のアミノ(N)末端、カルボキシ(C)末端、および第1膜貫通領域と第2膜貫通領域を連結する細胞外ループの3か所のアミノ酸配列にもとずく合成ペプチドに対する抗体を作製した。これに加えて、Kv1.2チャネルのアミノ(N)末端に対する抗体も作製した。2. Kv3.1aのalternative splicing variantであるKv3.1bをマウス小脳からクローン化した。Kv3.1bはC末端細胞内領域のみKv3.1aと異なる。3. Kv3.1bをGFP(Green fluorescent protein)標識し、Kv3.laと同時に培養神経細胞株に発現させた。Kv3.1aを認識する抗体、およびKv3.1bに付加したGFPを異なる蛍光波長で検出したところ両者の細胞内分布に差異がみられた。Kv3.1aはより微細な神経突起にまで広く分布するのに対して、Kv3.1bの局在は細胞体近傍に限られる傾向があった。4. 以上より、Kv3.1aおよびKv3.1bのチャネル蛋白は異なるアンカー(anchor)蛋白に会合している可能性が示唆される。今後Kv3.1aおよびKv3.1bのC末端領域を餌(bait)にしてtwo-hybridシステムのcDNAライブラリーをスクリーニングする予定である。5. 上記1の抗Kv1.2抗体を用いてラット感覚神経節の免疫染色を行ったところ、中型から大型の細胞体に強い染色が観察された。Kv1.2チャネルは触覚等の特定の感覚の伝達に大きく関与することが示唆された。研究課題/領域番号:09780720, 研究期間(年度):1997 – 1998出典：「膜電位依存性K^+チャネル(KV3.1)に会合する調節蛋白のcDNAクローニング」研究成果報告書　課題番号09780720（KAKEN：科学研究費助成事業データベース（国立情報学研究所））（https://kaken.nii.ac.jp/ja/grant/KAKENHI-PROJECT-9780720/)を加工して作

Dosimetric comparison of extended dose range film with ionization measurements in water and lung equivalent heterogeneous media exposed to megavoltage photons

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135483/1/acm20025.pd

Three-Dimensional Dose Model for the Comparison of 177Lu-HuCC49ΔCH2 and 177Lu-HuCC49 Radioimunotherapy in Mice Bearing Intraperitoneal Xenografts

Uptake and dose distributions in peritoneal LS174T colon tumor xenografts were compared for a humanized construct of the CC49 (HuCC49) high-affinity anti-TAG-72 monoclonal antibody and a construct with the CH2 region deleted (HuCC49ΔCH2), both labeled with 177Lu using a PA-DOTA bifunctional chelating agent and injected in the peritoneum. Tumors were resected and serially sectioned at 1 h, 4 h, 24 h, and 48 h postinjection. Between 5 and 24 (average 16) sections were retained per tumor for autoradiography. The typical section interval was 340 μm and thickness was 16 μm. Tumor sections were air dried and placed on film and/or phosphor screen. Section images were digitized at 100 μm resolution electronically (phosphor screen) or by laser densitometer (film). Section images were used to generate tumor surface descriptions and activity distributions by reconstructing the activity densities in three dimensions. Three-dimensional dose-rate calculations, performed using a point kernel for 177Lu, were used to prepare radial histograms describing the variation in dose rate as a function of distance from the tumor center to surface. At early times postinjection, the 177Lu-HuCC49ΔCH2 antibody displayed higher dose rates near the tumor surface compared to the 177Lu-HuCC49 antibody. At 24 h postinjection, dose rate distributions appeared similar for both antibodies and more uniform than at earlier times. The 177Lu-HuCC49ΔCH2 antibody indicated improved uniformity at 48 h postinjection. Cell survival calculations based on the three-dimensional dose rate distributions favored 177Lu-HuCC49ΔCH2 for equal injection activities. However the most significant effect was the greater injected dose tolerated for the 177Lu-HuCC49ΔCH2 antibody based on equivalent estimated bone marrow dose.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63413/1/108497803765036418.pd