• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to project page

2003 Fiscal Year Final Research Report Summary

Defference in physiological and mophological properties between jaw-closing and opening motoneurons

Research Project

Project/Area Number 14571777
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field Functional basic dentistry
Research InstitutionShowa University

Principal Investigator

INOUE Tomio  Showa University, School of Dentistry, Professor, 歯学部, 教授 (70184760)

Co-Investigator(Kenkyū-buntansha) OHATA Hisayuki  Showa University, School of Pharmaceutical Sciences, Associate Professor, 薬学部, 助教授 (00119166)
Project Period (FY) 2002 – 2003
Keywordstrigeminal / motoneuron / afterhyperpolarization / patch clamp / slice preparation / jaw-closing muscle / jaw-opening muscle
Research Abstract

Whole cell patch clamp recordings were made from masseter motoneurons (MaMNs) and digastric motoneurons (DiMNs) in neonatal rat brainstem slice preparations to study firing properties of jaw-closing and opening motoneurons. Input resistance and membrane time constant of MaMNs were smaller than those of DiMNs. Amplitude of the post-spike medium-duration afterhyperpolarization (mAHP) in MaMNs was smaller than that of DiMNs and duration of the mAHP in NaMNs was shorter than that of DiMNs. Decay time constant of the mAHP tail current in MaMNs was shorter than that in DiMNs. Ca^<2+> influx producing the mAHP through activation of Ca^<2+>-activated K^+ channel was monitored using Ca^<2+> imaging, in the presence of apamin ? -agatoxin IVA, ? -conotoxin CV1A and Ni^<2+>. The slope of the relationship between firing frequency (f) and membrane depolarization (V) induced by injection of 1-s current pulses was steeper in MaMNs than the slope in DiMNs. The slope of the f-V relationship were correlated with amplitude and duration of the mAHP and the difference in the slope of the f-V relationship between MaMNs and DiMNs was abolished by apamin. We conclude that smaller and shorter mAHP in MaMNs results in steeper slope of the the f-V relationship, compared with DiMNs. Such firing properties of jaw-closing and opening motoneurons might contribute to transduction of masticatory drive signal from central pattern generator of mastication to appropriate activities of jaw-closing and opening muscles.

  • Research Products

    (12 results)

All Other

All Publications (12 results)

  • [Publications] Inoue, T.: "Excitatory effects of noradrenaline on trigeminal motoneurons in rats."Dent.Jpn.. 38. 33-35 (2002)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Masuda, Y.: "Influence of oro-facial sensory input on the output of the cortical masticatory area in the anestheitzed rabbit."Exp.Brain Res.. 146. 501-510 (2002)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Inoue, T.: "Involvement of 5-HT_7 receptors in serotonergic effects on spike afterpotentials in presumed jaw-closing motoneurons of rats."Brain Res.. 954. 202-211 (2002)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Matsutani, K.: "Coeruleotrigeminal suppression of nociceptive sensorimotor function during inflammation in the craniofacial region of the cat."Brain Res.Bull.. 61. 73-80 (2003)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Tsuruoka, M.: "Coeruleospinal inhibition of nociceptive processing in the dorsal horn during unilateral hindpaw inflamation in the rat."Pain. 104. 353-361 (2003)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Tsuruoka, M.: "Coeruleotrigeminal inhibition of nociceptive processing in the rat trigeminal subnucleus caudalis."Brain Res.. 993. 146-153 (2003)

    • Description
      「研究成果報告書概要(和文)」より
  • [Publications] Inoue, T.: "Excitatory effects of noradrenaline on trigeminal motoneurons in rats."Dent.Jpn.. 38. 33-35 (2002)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Masuda, Y.: "Influence of oro-facial sensory input on the output of the cortical masticatory area in the anesthelized rabbit."Exp.Brain Res.. 146. 501-510 (2002)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Inoue, T.: "Involvement of 5-HT_7 receptors in serotonergic effects on spike afterpotentials in presumed jaw-closing motoneurons of rats."Brain Res.. 954. 202-211 (2002)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Matsutani, K.: "Coeruleotrigeminal suppression of nociceptive sensorimotor function during inflammation in the cranio facial region of the cat."Brain Res.Bull.. 61. 73-80 (2003)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Tsuruoka, M.: "Coeruleospinal inhibition of nociceptive processing in the dorsal horn during unilateral hindpaw inflamation in the rat."Pain. 104. 353-361 (2003)

    • Description
      「研究成果報告書概要(欧文)」より
  • [Publications] Tsuruoka, M.: "Coeruleotrigeminal inhibition of nociceplive processing in the rat trigeminal subnucleus caudalis."Brain Res.. 993. 146-153 (2003)

    • Description
      「研究成果報告書概要(欧文)」より

URL: 

Published: 2005-04-19  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi