| Project/Area Number |
11671855
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Functional basic dentistry
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| Research Institution | NIHON UNIVERSITY SCHOOL DENTISTRY AT MATSUDO |
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Principal Investigator |
SUGIYA Hiroshi NIHON UNIVERSITY SCHOOL OF DENTISTRY AT MATSUDO, DEPARTMENT OF PHYSIOLOGY, ASSOCIATE PROFESSOR, 松戸歯学部, 助教授 (20050114)
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| Co-Investigator(Kenkyū-buntansha) |
MICHIKAWA Hiromi NIHON UNIVERSITY SCHOOL OF DENTISTRY AT MATSUDO, DEPARTMENT OF PHYSIOLOGY, RESEARCH ASSISTANT, 松戸歯学部, 副手 (00277477)
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| Project Period (FY) |
1999 – 2000
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| Project Status |
Completed (Fiscal Year 2000)
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| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2000: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1999: ¥1,900,000 (Direct Cost: ¥1,900,000)
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| Keywords | SALIVARY GLANDS / NITRIC OXIDE / NITRIC OXIDE SYNTHASE / PAROTID GLAND / CALCIUM / CALMODULIN / CYCLIC GMP / 唾液腺 / 開口放出 / NOS / リン脂質 |
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| Research Abstract |
In parotid gland acinar cells, the secretory function is regulated by two main signaling pathways via muscarinic and β-adrenergic receptors. In this study, we investigated regulation of NO generation in rabbit parotid acinar cells to look for target molecules of nitric oxide/cyclic GMP signaling. In rabbit parotid acinar cells, muscarinic cholinergic agonist methaacholine induced an increase in intracellular Ca^<2+> concetration and provoked nitric oxide (NO) generation. On the other hand, α- and β-agonists, substance P, and VIP failed to induce Ca^<2+> mobilization and NO generation. Ca^<2+> mobilizing reagents such as thapsigargin and Ca^<2+> ionophore A 23187 mimicked the effect of methacholine on NO generation. Methacholine-induced NO generation was inhibited by the removal of extracellular Ca^<2+>. The immunoblot analysis indicated that the antibody against a neuronal type of nitrci oxide synthase (NOS) cross-reacted with NOS in the cytosol of the rabbit parotid gland. The immunofluorescent experiments showed that the NOS exists in the cytosol of acinar cells but less in the ductal cells. NOS was purified apporoximately 8,100-fold from the cytosolic fraction of the rabbit parotid glands by chromatographies on Sephacel S-200, DEAE-Sephacel, and 2', 5'-ADP-Sepharose. The NOS was NADPH- and tetrahydroxybiopterine-dependent enzyme and activated by Ca^<2+> at a physiologicl range in the presence of calmodulin. These results suggest that NO is generated by the activation of a neuronal type of NOS, which is regulated by the increase in intracellular Ca^<2+> levels induced by the activation of muscarinic receptors in rabbit parotid acinar cells.
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