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Sato T, Ando S, Aoki T, Arikawa H, Ezure S, Harada K, Hayamizu T, Inoue T, Ishikawa T, Itoh M, Kato K, Kato T, Kawamura H, Nataraj HS, Uchiyama A, Aoki T, Furukawa T, Hatakeyama A, Hatanaka K, Imai K, Murakami T, Shimizu Y, Wakasa T, Yoshida HP, Sakemi Y. Development of francium atomic beam for the search of the electron electric dipole moment. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146605019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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102
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Najafian K, Pettersson MS, Dynefors B, Shiromaru H, Matsumoto J, Tanuma H, Furukawa T, Azuma T, Hansen K. Radiative cooling of C7−. J Chem Phys 2014; 140:104311. [DOI: 10.1063/1.4867499] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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103
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Uchida T, Furukawa T, Iwata S, Yanagawa Y, Fukuda A. Selective loss of parvalbumin-positive GABAergic interneurons in the cerebral cortex of maternally stressed Gad1-heterozygous mouse offspring. Transl Psychiatry 2014; 4:e371. [PMID: 24618690 PMCID: PMC3966041 DOI: 10.1038/tp.2014.13] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/05/2014] [Accepted: 01/30/2014] [Indexed: 12/14/2022] Open
Abstract
Exposure to maternal stress (MS) and mutations in GAD1, which encodes the γ-aminobutyric acid (GABA) synthesizing enzyme glutamate decarboxylase (GAD) 67, are both risk factors for psychiatric disorders. However, the relationship between these risk factors remains unclear. Interestingly, the critical period of MS for psychiatric disorders in offspring corresponds to the period of GABAergic neuron neurogenesis and migration in the fetal brain, that is, in the late stage of gestation. Indeed, decrement of parvalbumin (PV)-positive GABAergic interneurons in the medial prefrontal cortex (mPFC) and hippocampus (HIP) has often been observed in schizophrenia patients. In the present study, we used GAD67-green fluorescent protein (GFP) knock-in mice (that is, mice in which the Gad1 gene is heterozygously deleted; GAD67(+/GFP)) that underwent prenatal stress from embryonic day 15.0 to 17.5 and monitored PV-positive GABAergic neurons to address the interaction between Gad1 disruption and stress. Administration of 5-bromo-2-deoxyuridine revealed that neurogenesis of GFP-positive GABAergic neurons, but not cortical plate cells, was significantly diminished in fetal brains during MS. Differential expression of glucocorticoid receptors by different progenitor cell types may underlie this differential outcome. Postnatally, the density of PV-positive, but not PV-negative, GABAergic neurons was significantly decreased in the mPFC, HIP and somatosensory cortex but not in the motor cortex of GAD67(+/GFP) mice. By contrast, these findings were not observed in wild-type (GAD67(+/+)) offspring. These results suggest that prenatal stress, in addition to heterozygous deletion of Gad1, could specifically disturb the proliferation of neurons destined to be PV-positive GABAergic interneurons.
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Arikawa H, Ando S, Aoki T, Ezure S, Harada K, Hayamizu T, Inoue T, Ishikawa T, Itoh M, Kawamura H, Kato K, Kato T, Uchiyama A, Aoki T, Furukawa T, Hatakeyama A, Hatanaka K, Imai K, Murakami T, Nataraj HS, Sato T, Shimizu Y, Wakasa T, Yoshida HP, Sakemi Y. Radioactive ion beam transportation for the fundamental symmetry study with laser-trapped atoms. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02A732. [PMID: 24593466 DOI: 10.1063/1.4852218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The search for the violation of the fundamental symmetry in a radioactive atom is the promising candidate for precision tests of the standard model and its possible extensions. The subtle signal arising from the symmetry violation is enhanced in heavy atoms, such as a francium (Fr). To realize high precision measurements, a large amount of radioactive isotopes is required. The Fr is produced via a nuclear fusion reaction using a melted gold target with a (18)O primary beam at Cyclotron and Radioisotope Center, Tohoku University. The maximum extraction efficiency of the Fr ion was achieved at approximately 35%. The beam line consists of an electrostatic deflector, three electrostatic quadrupole triplets to the measurement area at 10 m away from the reaction point, and several beam diagnosis systems. We optimized parameters of the beam line.
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105
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Inoue T, Ando S, Aoki T, Arikawa H, Ezure S, Harada K, Hayamizu T, Ishikawa T, Itoh M, Kato K, Kato T, Kawamura H, Nataraj H, Sato T, Uchiyama A, Aoki T, Furukawa T, Hatakeyama A, Hatanaka K, Imai K, Murakami T, Shimizu Y, Wakasa T, Yoshida H, Sakemi Y. Development of the Measurement System for the Search of an Electric Dipole Moment of the Electron with Laser-Cooled Francium Atoms. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146605008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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106
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Yang X, Furukawa T, Wakui T, Imamura K, Fujita H, Mitsuya Y, Hayasaka M, Ichikawa Y, Ishibashi Y, Shirai H, Ebara Y, Hatakeyama A, Wada M, Sonoda T, Ito T, Kobayashi T, Nishimura S, Nishimura M, Kondo Y, Yoneda K, Ueno H, Shinozuka T, Shimoda T, Asahi K, Matsuo Y. An effective method for trapping ion beams in superfluid helium for laser spectroscopy experiments. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146611041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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107
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Ichikawa Y, Chikamori M, Ohtomo Y, Hikota E, Sakamoto Y, Suzuki T, Bidinosti C, Inoue T, Furukawa T, Yoshimi A, Suzuki K, Nanao T, Miyatake H, Tsuchiya M, Yoshida N, Shirai H, Ino T, Ueno H, Matsuo Y, Fukuyama T, Asahi K. Search for electric dipole moment in 129Xe atom using active nuclear spin maser. EPJ WEB OF CONFERENCES 2014. [DOI: 10.1051/epjconf/20146605007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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108
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Li M, Kanda Y, Sekino Y, Furukawa T, Kurokawa J. A Novel Approach for Evaluation of Drug-Induced QT Prolongation using Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.3981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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109
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Furukawa T, Nakano H, Tanahashi T, Yoshihara K, Sudo N. Snoring is related to the elevation of morning blood pressure. Sleep Med 2013. [DOI: 10.1016/j.sleep.2013.11.292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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110
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Tanahashi T, Furukawa T, Hirayama K, Nakano H, Sudo N. Changes in subjective excessive daytime sleepiness after the Great East Japan Earthquake. Sleep Med 2013. [DOI: 10.1016/j.sleep.2013.11.685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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111
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Kanemura T, Kondo H, Hoashi E, Yoshihashi-Suzuki S, Yamaoka N, Horiike H, Furukawa T, Hirakawa Y, Ida M, Matsushita I, Wakai E. Fabrication and performance test of contact-type liquid level sensor for measuring thickness variation of liquid lithium jet in the IFMIF/EVEDA lithium test loop. FUSION ENGINEERING AND DESIGN 2013. [DOI: 10.1016/j.fusengdes.2013.05.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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112
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Takahashi W, Mori S, Furukawa T, Inaniwa T, Nakajima M, Shirai T, Noda K, Yamamoto N, Kamada T. Carbon Ion Scanning Lung Therapy (With Respiratory-Gated Phase Controlled Rescanning): Simulation Study for 4D Treatment Planning. Int J Radiat Oncol Biol Phys 2013. [DOI: 10.1016/j.ijrobp.2013.06.475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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113
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Mori S, Inaniwa T, Furukawa T, Zenklusen S, Shirai T, Noda K. Effects of a difference in respiratory cycle between treatment planning and irradiation for phase-controlled rescanning and carbon pencil beam scanning. Br J Radiol 2013; 86:20130163. [PMID: 23833034 DOI: 10.1259/bjr.20130163] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To evaluate the impact of variation in respiratory cycle between treatment planning and irradiation for pencil beam scanning and phase-controlled rescanning (PCR) on the resulting dose distribution, we conducted a simulation study based on four-dimensional CT (4DCT) data for lung cancer patients. METHODS 4DCT data were acquired for seven patients with lung tumours. Treatment planning was designed to ensure the delivery of 95% of the prescribed dose to the clinical target volume in respective phases of the 4DCT by taking account of intrafractional beam range variations. Carbon ion pencil beam scanning dose distributions were calculated for various respiratory cycles that differed from the reference respiration (=4.4 s) but which stayed regular during irradiation. The number of rescannings was changed to 1, 4 or 8 times. PCR was correlated with the gating window in treatment planning to calculate the beam weighting map. RESULTS 8×PCR improved dose conformation to the target for all irradiation respiratory cycles. Minimum dose (Dmin) and lowest dose encompassing 95% of the target (D95) values with 4×PCR were decreased from 94.1% and 98.1% to 88.4% and 93.5% with an altered irradiation respiratory cycle of 2.4 s. However, these values were improved with 8×PCR to over 94.9% for Dmin and 98.6% for D95 for respective irradiation respiratory cycles. CONCLUSION Pencil beam scanning treatment with eight or more PCRs consistently improved dose conformation for moving lung targets even when different respiratory cycles were used for treatment planning and irradiation. ADVANCES IN KNOWLEDGE Scanning treatment with eight or more rescannings consistently improved dose homogeneity to a moving target even though respiratory cycles varied during treatment.
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114
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Kitano M, Kitano S, Ishizu M, Furukawa T, Yoshikawa T, Fujita K, Katashima Y, Sato C, Saito A, Nishioka A, Sekiguchi M, Azuma N, Hashimoto N, Tsunoda S, Matsui K, Iwasaki T, Sano H. SAT0119 Effect of Abatacept on Bone Homeostasis and Osteopontin in Rheumatoid Arthritis. Ann Rheum Dis 2013. [DOI: 10.1136/annrheumdis-2013-eular.1845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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115
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Okata S, Yuasa S, Yamane T, Furukawa T, Fukuda K. The generation of induced pluripotent stem cells from a patient with KCNH2 G603D, without LQT2 disease associated symptom. JOURNAL OF MEDICAL AND DENTAL SCIENCES 2013; 60:17-22. [PMID: 23917959] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 11/16/2012] [Indexed: 06/02/2023]
Abstract
The long QT syndrome type 2 (LQT2) is inheritable life threatening arrhythmic disorder and one of the most common genetic variants in long QT syndrome. There are some indications for treatment of the patients with LQT2 but it is impossible to completely prevent fatal arrhythmia. To develop novel therapy for the patients with LQT2, it has been desired to generate diseasespecific and patient-specific disease model. Human induced pluripotent stem (iPS) cells are somatic cell-derived pluripotent stem cells with infinite proliferation ability and multipotency. Patient-specific iPS cells can be derived from patient somatic cells, have all genomic information encoded in patient's genome including mutation and all SNPs, and can be ideal disease models of the patients. To generate disease model for LQT2 by iPS cells, we should firstly generate iPS cells from the patient with LQT2 and confirm the genomic mutation in iPS cells. In this study, we showed the successful generation of iPS cells from a patient with KCNH2 G603D mutation. The patient specific iPS cells properly expressed stem cell markers, such as NANOG and OCT3/4. We also confirmed that the KCNH2 G603D (G1808A) mutation was taken over in patient specific iPS cells. These patient-specific iPS cells may contribute to the future analysis for disease pathogenesis and drug innovation.
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Sonoda T, Wada M, Tomita H, Sakamoto C, Takatsuka T, Noto T, Iimura H, Matsuo Y, Kubo T, Shinozuka T, Wakui T, Mita H, Naimi S, Furukawa T, Itou Y, Schury P, Miyatake H, Jeong S, Ishiyama H, Watanabe Y, Hirayama Y. Development of a gas cell-based laser ion source for RIKEN PALIS. ACTA ACUST UNITED AC 2013. [DOI: 10.1007/s10751-013-0817-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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117
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Kawakami H, Koya T, Kagamu H, Kimura Y, Sakamoto H, Yamabayashi C, Furukawa T, Sakagami T, Miyabayashi T, Hasegawa T, Suzuki E, Narita I. IL-17 eliminates therapeutic effects of oral tolerance in murine airway allergic inflammation. Clin Exp Allergy 2013; 42:946-57. [PMID: 22909166 DOI: 10.1111/j.1365-2222.2012.04006.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Oral tolerance is a classically used strategy for antigen-specific systemic immunotherapy. However, the roles of IL-17 in modification of oral tolerance are not yet understood. OBJECTIVE To define the effects of IL-17 on the modification of oral tolerance, the effects of transfer of Th17 cells, administration of IL-17 or anti-IL-17 antibody (αIL-17Ab) to a murine allergic airway inflammation model were investigated. METHODS Mice sensitized to and challenged with OVA, received OVA feeding, followed by OVA challenges. Transfer of Th17 cells, administration of IL-17 or αIL-17Ab were executed during OVA feeding. Airway hyperresponsiveness (AHR), airway inflammation, Th2 cytokine response and lung pathology were assessed. RESULTS Administration of IL-17 as well as transfer of Th17 cells aggravated AHR and airway allergic inflammation as compared with the findings in mice subjected to OVA feeding alone, whereas administration of αIL-17Ab ameliorated AHR and airway eosinophilia. The effects of Th17 transfer were presumably attributable to augmentation of endogenous IL-6 production in gut. The number of Foxp3-positive regulatory T (Treg) cells in lungs and Payer's patches was increased in the OVA fed mice, whereas the number of these cells was decreased in the mice subjected to OVA feeding + Th17 cell transfer. Neutralization of IL-6 by monoclonal antibody in the mice subjected to OVA feeding + transfer of Th17 cells restored the effects of oral tolerance. CONCLUSIONS AND CLINICAL RELEVANCE These data suggest that IL-17 may inhibit the induction of tolerance to antigen through, at least in part augmenting IL-6 production, thereby suppressing the expansion of Treg cells.
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Abstract
Although cardiac arrhythmia had long been considered a predominantly male syndrome, it is now clear that arrhythmia is also a primary cause of mortality in women. Notably, the manifestation of specific arrhythmia syndromes appears to be gender specific. In particular, female sex is an independent risk factor for development of torsade de pointes (TdP) arrhythmias not only in congenital long QT syndromes but also in acquired long QT syndromes which occur as adverse effects of existing drugs. Males, on the other hand, are more likely to develop Brugada syndrome. Recent clinical and experimental studies suggest that these differences may stem from intrinsic sex differences in cardiac tissue. These include fundamental electrical differences resulting from variable ion channel expression and diverse sex hormonal regulation via long-term genomic and acute nongenomic pathways, and sex differences in drug responses and metabolisms. Undoubtedly, determining the effect of gender on cardiac function will be difficult and require sophisticated methodologies. However, gender differences underlying predilection to distinct arrhythmia syndromes must be revealed so that new therapeutic strategies that take gender into account can be applied to at-risk patients.
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119
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Kurokawa J, Kodama M, Goryoda S, Furukawa T. Involvement of PDE2 in a Localized Regulation of the L-Type Ca2+ Channels by Progesterone. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.1578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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120
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López-Redondo F, Kurokawa J, Nomura F, Kaneko T, Hamada T, Yasuda K, Furukawa T. Human ES- and Induced Pluripotent Stem-Derived Cardiomyocytes. A Comparative Electrophysiological Study. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.1658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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121
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Kurokawa J, Furukawa T. Non-genomic Action of Sex Steroid Hormones and Cardiac Repolarization. Biol Pharm Bull 2013; 36:8-12. [DOI: 10.1248/bpb.b212021] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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122
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Asayama M, Kurokawa J, Shirakawa K, Okuyama H, Kagawa T, Okada JI, Sugiura S, Hisada T, Furukawa T. Effects of an hERG Activator, ICA-105574, on Electrophysiological Properties of Canine Hearts. J Pharmacol Sci 2013; 121:1-8. [DOI: 10.1254/jphs.12220fp] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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123
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Oishi S, Sasano T, Tateishi Y, Tamura N, Isobe M, Furukawa T. Stretch of atrial myocytes stimulates recruitment of macrophages via ATP released through gap-junction channels. J Pharmacol Sci 2012. [PMID: 23196902 DOI: 10.1254/jphs.12202fp] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
Atrial inflammation is critical to atrial fibrillation initiation and progression. Although left atrial dilatation is a risk factor for atrial fibrillation, the mechanism linking atrial dilatation and inflammation is unclear. We evaluated the mechanisms underlying infiltration of macrophages induced by stretch of atrial myocytes. Murine macrophages were co-cultured with HL-1 murine atrial myocyte-derived cells. Mechanical stretch applied to atrial myocytes induced transwell macrophage migration. The gap junction-channel blocker carbenoxolone and the non-specific ATP-signaling modifiers apyrase and pyridoxal-phosphate-6-azophenyl-2',4'-disulfonate inhibited the enhanced migration. Mechanical stretch of atrial myocytes induced transient increase in extracellular ATP concentration, which was inhibited by carbenoxolone. siRNA knockdown of pannexin-2 inhibited ATP release and macrophage migration. Mice underwent transverse aortic constriction or sham procedure. Transverse aortic constriction procedure induced macrophage infiltration. Daily carbenoxolone administration significantly inhibited macrophage infiltration in the atrium. Thus, mechanical stretch of atrial myocytes induces macrophage migration by ATP released through gap-junction channels, at least in part, in vitro. Administering a gap junction family-channel blocker inhibited this inflammatory change in vivo.
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Omori Y, Chaya T, Furukawa T. Photoreceptor degeneration caused by defects of a ciliary kinase. Cilia 2012. [PMCID: PMC3555877 DOI: 10.1186/2046-2530-1-s1-p96] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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125
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Wei B, Kumada T, Furukawa T, Inoue K, Watanabe M, Sato K, Fukuda A. Pre- and post-synaptic switches of GABA actions associated with Cl- homeostatic changes are induced in the spinal nucleus of the trigeminal nerve in a rat model of trigeminal neuropathic pain. Neuroscience 2012; 228:334-48. [PMID: 23103796 DOI: 10.1016/j.neuroscience.2012.10.043] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2012] [Revised: 10/16/2012] [Accepted: 10/19/2012] [Indexed: 02/01/2023]
Abstract
Although trigeminal neuropathic pain is one of the most common chronic pain syndromes, the etiology is still unknown. Here, a rat model was generated using chronic constrictive injury (CCI) with ligation of the infraorbital nerve to test the hypothesis that collapse of chloride homeostasis in trigeminal neurons causes impairment of γ-aminobutyric acid-ergic (GABAergic) inhibition and induces trigeminal allodynia. Rats showed a reduction and increase in pain threshold and pain response scores, respectively, to mechanical stimulation, 1 and 3weeks after CCI. In situ hybridization and immunohistochemical analysis showed that inward-directed Na(+), K(+)-2Cl(-) cotransporter (NKCC1) mRNA and protein were upregulated in the small-sized and large-sized primary neurons in the injured side of the trigeminal ganglion and in the peripherin-positive terminal, respectively, for the first 2weeks, while outward-directed K(+)-Cl(-) cotransporter (KCC2) mRNA and protein were downregulated in secondary relay neurons on the injured side of the spinal trigeminal nucleus caudalis (Sp5C). Optical imaging of evoked synaptic responses using a voltage-sensitive dye revealed that pre- and post-synaptic GABA actions were disinhibited and excitatory in the injured side, respectively, but inhibited in the sham-operated side of the Sp5C. This downregulation of KCC2 in the Sp5C may result in an excitatory switch by impairing postsynaptic GABA inhibition. GABA-mediated presynaptic disinhibition was attenuated by bumetanide, suggesting that NKCC1 upregulation in primary neurons may facilitate pain transmission by presynaptic GABAergic depolarization. Such Cl(-) homeostatic disruption resulting in perturbation of the inhibitory system possibly increases pain transmission, which may underlie the pathophysiology of trigeminal neuropathic pain.
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