Yasumasa Okada

Summary

Affiliation: Keio University
Country: Japan

Publications

  1. pmc Preinspiratory calcium rise in putative pre-Botzinger complex astrocytes
    Yasumasa Okada
    Division of Internal Medicine and Laboratory of Electrophysiology, Murayama Medical Center, 2 37 1 Gakuen, Musashimurayama, Tokyo 208 0011, Japan
    J Physiol 590:4933-44. 2012
  2. pmc Effects of long-term low-dose oxygen supplementation on the epithelial function, collagen metabolism and interstitial fibrogenesis in the guinea pig lung
    Takuya Aoki
    Respiratory Division, Department of Internal Medicine, School of Medicine, Tokai University, Isehara, Japan
    Respir Res 9:37. 2008
  3. ncbi request reprint Significance of extracellular potassium in central respiratory control studied in the isolated brainstem-spinal cord preparation of the neonatal rat
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Tsukigase 380 2, Izu City, Shizuoka ken 410 3215, Japan
    Respir Physiol Neurobiol 146:21-32. 2005
  4. ncbi request reprint [Localization and function of the brainstem neuronal mechanism for respiratory control]
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Izu, Japan
    Nihon Shinkei Seishin Yakurigaku Zasshi 27:207-14. 2007
  5. ncbi request reprint Electrical stimulation of the rabbit pulmonary artery increases respiratory output
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Amagiyugashima cho, Tagata gun, Shizuoka ken 410 3215, Japan
    Respir Physiol Neurobiol 140:209-17. 2004
  6. ncbi request reprint Chemosensitive neuronal network organization in the ventral medulla analyzed by dynamic voltage-imaging
    Yasumasa Okada
    Keio University Tsukigase Rehabilitation Center, Department of Medicine
    Adv Exp Med Biol 605:353-7. 2008
  7. ncbi request reprint Anatomical arrangement of hypercapnia-activated cells in the superficial ventral medulla of rats
    Yasumasa Okada
    Department of Medicine, Keio University, Tsukigase Rehabilitation Center, Shizuoka ken 410 3293, Japan
    J Appl Physiol (1985) 93:427-39. 2002
  8. doi request reprint Anatomical changes of phrenic motoneurons during development
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Shizuoka, Japan
    Adv Exp Med Biol 669:33-6. 2010
  9. ncbi request reprint Cytoarchitecture of central chemoreceptors in the mammalian ventral medulla
    Y Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Tagata gun Tsukigase 380 2, Amagiyugashima cho, Shizuoka ken 410 3293, Japan
    Respir Physiol 129:13-23. 2001
  10. doi request reprint Anatomical architecture and responses to acidosis of a novel respiratory neuron group in the high cervical spinal cord (HCRG) of the neonatal rat
    Y Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Izu, Japan
    Adv Exp Med Biol 648:387-94. 2009

Collaborators

Detail Information

Publications37

  1. pmc Preinspiratory calcium rise in putative pre-Botzinger complex astrocytes
    Yasumasa Okada
    Division of Internal Medicine and Laboratory of Electrophysiology, Murayama Medical Center, 2 37 1 Gakuen, Musashimurayama, Tokyo 208 0011, Japan
    J Physiol 590:4933-44. 2012
    ..These findings raise the possibility that astrocytes in the preBötC are actively involved in respiratory rhythm generation in rhythmically active slices...
  2. pmc Effects of long-term low-dose oxygen supplementation on the epithelial function, collagen metabolism and interstitial fibrogenesis in the guinea pig lung
    Takuya Aoki
    Respiratory Division, Department of Internal Medicine, School of Medicine, Tokai University, Isehara, Japan
    Respir Res 9:37. 2008
    ..This study was designed to clarify the effects of long-term low-dose oxygen inhalation on pulmonary epithelial function, edema formation, collagen metabolism, and alveolar fibrosis...
  3. ncbi request reprint Significance of extracellular potassium in central respiratory control studied in the isolated brainstem-spinal cord preparation of the neonatal rat
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Tsukigase 380 2, Izu City, Shizuoka ken 410 3215, Japan
    Respir Physiol Neurobiol 146:21-32. 2005
    ..It is concluded that [K+]ECF is of importance in the maintenance of respiratory rhythm and central chemosensitivity...
  4. ncbi request reprint [Localization and function of the brainstem neuronal mechanism for respiratory control]
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Izu, Japan
    Nihon Shinkei Seishin Yakurigaku Zasshi 27:207-14. 2007
    ....
  5. ncbi request reprint Electrical stimulation of the rabbit pulmonary artery increases respiratory output
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Amagiyugashima cho, Tagata gun, Shizuoka ken 410 3215, Japan
    Respir Physiol Neurobiol 140:209-17. 2004
    ..Further studies to anatomically identify the neural substrate and clarify its physiological role in respiratory control are necessary...
  6. ncbi request reprint Chemosensitive neuronal network organization in the ventral medulla analyzed by dynamic voltage-imaging
    Yasumasa Okada
    Keio University Tsukigase Rehabilitation Center, Department of Medicine
    Adv Exp Med Biol 605:353-7. 2008
    ..We propose a neuronal network organization model for central chemoreceptors...
  7. ncbi request reprint Anatomical arrangement of hypercapnia-activated cells in the superficial ventral medulla of rats
    Yasumasa Okada
    Department of Medicine, Keio University, Tsukigase Rehabilitation Center, Shizuoka ken 410 3293, Japan
    J Appl Physiol (1985) 93:427-39. 2002
    ..The chemosensitivity of surface cells (possible type I cells) surrounding vessels was confirmed electrophysiologically in slice preparations. We suggest that this characteristic anatomical structure may be the central chemoreceptor...
  8. doi request reprint Anatomical changes of phrenic motoneurons during development
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Shizuoka, Japan
    Adv Exp Med Biol 669:33-6. 2010
    ..During development the sizes and surface areas of phrenic motoneurons are increased with changes in dendritic morphology...
  9. ncbi request reprint Cytoarchitecture of central chemoreceptors in the mammalian ventral medulla
    Y Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Tagata gun Tsukigase 380 2, Amagiyugashima cho, Shizuoka ken 410 3293, Japan
    Respir Physiol 129:13-23. 2001
    ..Among various unanswered questions in central chemosensitivity studies, physiological significance of surface cells and surface extending dendrites is the most important topic, and must be thoroughly investigated...
  10. doi request reprint Anatomical architecture and responses to acidosis of a novel respiratory neuron group in the high cervical spinal cord (HCRG) of the neonatal rat
    Y Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Izu, Japan
    Adv Exp Med Biol 648:387-94. 2009
    ..We suggest that the HCRG composes a local respiratory neuronal network consisting of interneurons and motoneurons and plays an important role in respiratory augmentation in response to acidosis...
  11. doi request reprint The central respiratory chemoreceptor: where is it located?-Invited article
    Y Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Izu, Japan
    Adv Exp Med Biol 648:377-85. 2009
    ..Definitive identification of chemosensitive sites and chemoreceptor cells needs further studies...
  12. ncbi request reprint A neuronal mechanism of propofol-induced central respiratory depression in newborn rats
    Masanori Kashiwagi
    Department of Anesthesiology, School of Medicine, Keio University, Tokyo, Japan
    Anesth Analg 99:49-55. 2004
    ..It is likely that the GABAA receptor-mediated hyperpolarization of preinspiratory neurons serves as the neuronal basis of propofol-induced respiratory depression in the newborn rat...
  13. ncbi request reprint Effects of neuromuscular blocking agents on central respiratory chemosensitivity in newborn rats
    Shigeki Sakuraba
    Department of Anesthesiology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku ku, Tokyo 160 8582, Japan
    Biol Res 38:225-33. 2005
    ..Our results demonstrate that neuromuscular blocking agents inhibit CO2-excited tonic firing neurons and attenuate respiratory CO2 responsiveness...
  14. doi request reprint Spatiotemporal and anatomical analyses of P2X receptor-mediated neuronal and glial processing of sensory signals in the rat dorsal horn
    Ryoma Aoyama
    Department of Orthopaedic Surgery, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku ku, Tokyo 160 8582, Japan
    Pain 152:2085-97. 2011
    ..Astrocytes are involved in sensitization of sensory network activity more importantly in the superficial than in the deep layer...
  15. ncbi request reprint Respiratory and metabolic acidosis differentially affect the respiratory neuronal network in the ventral medulla of neonatal rats
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Izu, Japan
    Eur J Neurosci 26:2834-43. 2007
    ..We suggest that they differently influence the coupling states between the pFRG/RTN and preBötC/VRG...
  16. doi request reprint Antagonism of morphine-induced central respiratory depression by donepezil in the anesthetized rabbit
    Miki Tsujita
    Department of Anesthesiology, School of Medicine, Keio University, Tokyo, Japan
    Biol Res 40:339-46. 2007
    ..These findings indicate that systemically administered donepezil partially restores morphine-induced respiratory depression and morphine-deteriorated phrenic nerve apnea threshold in the anesthetized rabbit...
  17. ncbi request reprint Functional connection from the surface chemosensitive region to the respiratory neuronal network in the rat medulla
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Tsukigase 380 2, Izu City, Shizuoka ken 410 3215 Japan
    Adv Exp Med Biol 551:45-51. 2004
  18. doi request reprint Time-course of ventilation, arterial and pulmonary CO(2) tension during CO (2) increase in humans
    Toru Satoh
    Department of Medicine, Kyorin University School of Medicine, Mitakashi, Tokyo, Japan
    Adv Exp Med Biol 758:63-70. 2012
    ....
  19. doi request reprint Age-dependent involvement of ATP-sensitive potassium channel Kir6.2 in hypoxic ventilatory depression of mouse
    Yoshitaka Oyamada
    Department of Pulmonary Medicine, School of Medicine, Keio University, 35 Shinano machi, Shinjuku ku, Tokyo, Japan
    Respir Physiol Neurobiol 162:80-4. 2008
    ..12 in N(2)). These findings suggest that Kir6.2 is involved in HVD of the mouse at a certain point during the postnatal development...
  20. ncbi request reprint The cell-vessel architecture model for the central respiratory chemoreceptor
    Yasumasa Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Izu City, Shizuoka 410 3215 Japan
    Adv Exp Med Biol 580:233-8; discussion 351-9. 2006
  21. ncbi request reprint Effects of neuromuscular blocking agents on central respiratory control in the isolated brainstem-spinal cord of neonatal rat
    Shigeki Sakuraba
    Department of Anesthesiology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku ku, Tokyo 160 8582, Japan
    Neurosci Res 47:289-98. 2003
    ....
  22. ncbi request reprint Potassium channels in the central control of breathing
    Yoshitaka Oyamada
    Department of Pulmonary Medicine, School of Medicine, Keio University, Shinjuku, Tokyo, Japan
    Adv Exp Med Biol 580:339-44; discussion 351-9. 2006
  23. doi request reprint Effects of arundic acid, an astrocytic modulator, on the cerebral and respiratory functions in severe hypoxia
    Isato Fukushi
    Department of Biomedical Engineering, Graduate School of Science and Engineering, Toyo University, 2100 Kujirai, Kawagoe, Saitama 350 8585, Japan Clinical Research Center, Murayama Medical Center, 2 37 1 Gakuen, Musashimurayama, Tokyo 208 0011, Japan
    Respir Physiol Neurobiol 226:24-9. 2016
    ..Astrocytic activation in hypoxia may counteract both cerebral and ventilatory suppression. ..
  24. ncbi request reprint Role of the pons in hypoxic respiratory depression in the neonatal rat
    Y Okada
    Institut fur Physiologie, Ruhr Universitat Bochum, Germany
    Respir Physiol 111:55-63. 1998
    ..In addition, we show that the respiratory modulatory functions of the diencephalon (facilitating) and midbrain (inhibitory) are already expressed at the time of birth...
  25. ncbi request reprint Optical mapping of pontine chemosensitive regions of neonatal rat
    Yoko Ito
    Department of Medicine, School of Medicine, Keio University, 35 Shinano machi, Shinjuku ku, Tokyo 160 8582, Japan
    Neurosci Lett 366:103-6. 2004
    ..These results suggest that the optical recording method is applicable to identification of potentially chemosensitive areas, which deserve further electrophysiological analysis, and that the A5 area could be chemosensitive...
  26. ncbi request reprint Synaptic blockade plays a major role in the neural disturbance of experimental spinal cord compression
    Hideaki Yoshida
    Department of Orthopaedic Surgery, School of Medicine, Keio University, Tokyo, Japan
    J Neurotrauma 20:1365-76. 2003
    ..We suggest that a disturbance of synaptic transmission plays an important role in the pathophysiological mechanisms of spinal cord compression, at least under in vitro experimental conditions of juvenile rats...
  27. ncbi request reprint Mixed venous CO2 and ventilation during exercise and CO2-rebreathing in humans
    Toru Satoh
    Department of Medicine, National Cardiovascular Center, Suita, Osaka, Japan
    Adv Exp Med Biol 551:269-74. 2004
  28. ncbi request reprint Optical recording of the neuronal activity in the brainstem-spinal cord: application of a voltage-sensitive dye
    Y Okada
    Department of Medicine, Keio University Tsukigase Rehabilitation Center, Shizuoka, Japan
    Adv Exp Med Biol 499:113-8. 2001
    ..Optical recording techniques using voltage-sensitive dyes will be more importantly applied in the study of central respiratory control (e.g., mechanisms of respiratory rhythm generation) in the near future...
  29. doi request reprint Respiratory Toxicity of Dimethyl Sulfoxide
    Kotaro Takeda
    Clinical Research Center, National Hospital Organization Murayama Medical Center, 2 37 1 Gakuen, Musashimurayama, 208 0011, Tokyo, Japan
    Adv Exp Med Biol 885:89-96. 2016
    ..The study delineates the safety profile of DMSO regarding the respiratory function which is essential for maintaining proper tissue oxygenation. Caution should be exercised concerning dose concentration of DMSO...
  30. ncbi request reprint Anisotropic conduction properties in canine atria analyzed by high-resolution optical mapping: preferential direction of conduction block changes from longitudinal to transverse with increasing age
    Takahiro Koura
    Cardiopulmonary Division, Department of Medicine, Keio University School of Medicine, Tokyo, Japan
    Circulation 105:2092-8. 2002
    ..We investigated the age-dependent changes of structural and functional anisotropy in isolated right atria from infant (1 to 2 months), young (6 to 12 months), and old (6 to 10 years) dogs...
  31. ncbi request reprint Brevican is degraded by matrix metalloproteinases and aggrecanase-1 (ADAMTS4) at different sites
    H Nakamura
    Department of Pathology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku ku, Tokyo 160 0016, Japan
    J Biol Chem 275:38885-90. 2000
    ....
  32. ncbi request reprint Ischemia-induced disturbance of neuronal network function in the rat spinal cord analyzed by voltage-imaging
    K Fukuda
    Department of Orthopaedic Surgery, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku ku, Tokyo 160 8582, Japan
    Neuroscience 140:1453-65. 2006
    ..Severe ischemic stress induces irreversible dysfunction of neurons accompanied by eventual cell death in both dorsal and ventral horns...
  33. doi request reprint Spatiotemporal organization of frog respiratory neurons visualized on the ventral medullary surface
    Yoshitaka Oku
    Department of Physiology, Hyogo College of Medicine, Nishinomiya, Hyogo 663 8501, Japan
    Respir Physiol Neurobiol 161:281-90. 2008
    ..We conclude that the pattern generator but not the rhythm generator of lung burst in the frog involves glycinergic mechanisms and lies as longitudinal columns in the reticular formation of the ventrolateral medulla...
  34. pmc Postnatal developmental changes in activation profiles of the respiratory neuronal network in the rat ventral medulla
    Yoshitaka Oku
    Department of Physiology, Hyogo College of Medicine, Nishinomiya, Hyogo 663 8501, Japan
    J Physiol 585:175-86. 2007
    ..The changes in spatiotemporal activation profiles of the pFRG neurones may reflect changes in the mode of coupling of the two respiratory rhythm generators...
  35. ncbi request reprint Electrophysiological and morphological characteristics of GABAergic respiratory neurons in the mouse pre-Bötzinger complex
    Shun Ichi Kuwana
    Department of Physiology, Teikyo University School of Medicine, Kaga 2 11 1, Itabashi ku, Tokyo 173 8605, Japan
    Eur J Neurosci 23:667-74. 2006
    ....
  36. ncbi request reprint Mechanism of propofol-induced central respiratory depression in neonatal rats anatomical sites and receptor types of action
    Masanori Kashiwagi
    Department of Anesthesiology, School of Medicine, Keio University, Tokyo, 160 8582 Japan
    Adv Exp Med Biol 551:221-6. 2004
  37. ncbi request reprint Role of GABA in central respiratory control studied in mice lacking GABA-synthesizing enzyme 67-kDa isoform of glutamic acid decarboxylase
    Shun Ichi Kuwana
    Department of Physiology, Teikyo University School of Medicine, Tokyo, 173 8605 Japan
    Adv Exp Med Biol 551:157-63. 2004