Project/Area Number |
06670131
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
General pharmacology
|
Research Institution | National Institute of Health Sciences |
Principal Investigator |
KAWANISHI Toru National Institute of Health Sciences, Division of Biological Chemistry and Biologicals, Chief, 生物薬品部, 室長 (40124383)
|
Co-Investigator(Kenkyū-buntansha) |
HAYAKAWA Takao National Institute of Health Sciences, Division of Biological Chemistry and Biol, 生物薬品部, 部長 (50124392)
YOKOTA Isue National Institute of Health Sciences, Division of Biological Chemistry and Biol, 生物薬品部, 主任研究官
OHTA Miyako National Institute of Health Sciences, Division of Biological Chemistry and Biol, 生物薬品部, 主任研究官
TAKAHASHI Michito National Institute of Health Sciences, Division of Pathology, Director, 病理部, 部長 (30080005)
TOYODA Kazuhiro National Institute of Health Sciences, Division of Pathology, Researcher, 病理部, 研究員
畝山 智香子 国立衛生試験所, 病理部, 研究員 (30206817)
|
Project Period (FY) |
1994 – 1995
|
Project Status |
Completed (Fiscal Year 1995)
|
Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1995: ¥1,000,000 (Direct Cost: ¥1,000,000)
Fiscal Year 1994: ¥1,100,000 (Direct Cost: ¥1,100,000)
|
Keywords | confocal laser scanning microscopy / calcium ion / calcium wave / fluorescent probes / liver / hepatocyte |
Research Abstract |
The mechanism of calcium waves was analyzed in primary cultured rat hepatocytes using rapid scanning confocal microscopy. Hormonal stimulations by phenylephrine, vasopressin and ATP and a proliferative stimulation by HGF induced repetitive increases of cytosolic free Ca^<2+> concentration ([Ca^<2+>] i). The increases in [Ca^<2+>] i originated from a specific same origin adjacent to the cell membrane and propagated across the cell like waves. In each cell the locus where the Ca^<2+> waves induced by an agonist wre originated was the same as those where the Ca^<2+> waves induced by the other agonists were originated. There was also a correlation in the peak height in the Ca^<2+> weaves induced by different agonists in each cell. However, there was no correlation between sensitivity of each cell to the agonists, which were measured as latent periods prior to Ca^<2+> rises after an addition of the agonists. The kinetic analysis of Ca^<2+> transients in several small regions in the cells suggested the followings : (1) the spatial patterns of Ca^<2+> waves were not depending on the increases of inostiol 1,4,5 triphosphate (Ins (1,4,5) P_3) in the limited parts of the cells and its propagation, but on the distribution of Ins (1,4,5) P_3-sensitive Ca^<2+> pools ; (2) the sensitivity of each cell to agonists was highly depending on the concentration of Ins (1,4,5) P_3 formed.
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