1997 Fiscal Year Final Research Report Summary
Ion channel function and regulation of airway structural cells
| Project/Area Number |
07457144
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Respiratory organ internal medicine
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| Research Institution | Tohoku University |
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Principal Investigator |
SHIMURA Sanae Tohoku Univ.Hospital, Lecturer, 医学部・附属病院, 講師 (20154312)
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| Co-Investigator(Kenkyū-buntansha) |
KAKUTA Yasunori Tohoku Univ.Hospital, Research Associate, 医学部・附属病院, 助手 (80142933)
OKAYAMA Hiroshi Tohoku Univ.Hospital, Research Associate, 医学部・附属病院, 助手 (10160730)
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| Project Period (FY) |
1995 – 1997
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| Keywords | Airway Epithelial Cells / Airway Gland Cells / Airway Smooth muscle cells / Patch clamp method / Ion channel / Membrane Potentials / IP_3 / Cyclic ADP rihore |
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| Research Abstract |
Airways consist of epithelial cells, gland cells, smooth muscle cells and nerves. We examined the function and regulation of ion channels of these structural cells and obtained the following findings.
1) In superficial epithelium, non-ciliated cells play main role in chloride (Cl^-) secretion rather than do ciliated cells.
2) Cyclic AMP-dependent Cl^- channels (CFTR) newly develop in superficial epithelial cells in bronchitic airways.
3) In gland cells, both IP_3-sensitive and cyclic ADP ribose-sensitive Ca^<2+>-pools are necessary for initiating the activation of Cl^- channels.
4) Cholinergic stimulation induces depolarization of membrane potentials in airway smooth muscle cells, while both histamine and endothelin induce the mambrane hyperpolarization through the activation of K_<DR> channels.
5) GABA receptor-operated Cl^- channels are active in airway ganglion cells.
6) Both Na^+/K^+/Cl^- cotransporter and Na^+/K^+ pump are related to Cl^- secretion in superficial epithelial cells and gland cells.
7) Glucocorticoid suppresses the function of Cl^- channels in both superficial epithelial cells and gland cells.
8) In rabbit epithelial cells, Ca^<2+>-sensitive Cl^- channelsmainly operate, while CFTR mainly does in human superficial epithelium. PGE_2-release from human epithelium modulates both gland cell and smooth muscle cell functions, but does not in animal airways.
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