1995 Fiscal Year Final Research Report Summary
Cross talk between tyrosine kinase and protein kinase C in the regulatory mechanism of salivary secretion.
Project/Area Number |
06671867
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
Functional basic dentistry
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Research Institution | Health Sciences University of Hokkaido |
Principal Investigator |
ICHIDA Tokuro Professor, School of Dentistry Health Sciences University of Hokkaido, 歯学部, 教授 (50001003)
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Co-Investigator(Kenkyū-buntansha) |
TAKUMA Taishin Assistant Professor, School of Dentistry Health Sciences University of Hokkaido, 歯学部, 講師 (40095336)
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Project Period (FY) |
1994 – 1995
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Keywords | Genistein ; / Tyrosine kinase inhibitor ; / Tyrosine phosphorylation ; / Amylase exocytosis ; / Parotid acinar cell. |
Research Abstract |
In pancreatic acinar cells, Ca-mobilizing agonists such as cholecystokinin and acetylcholine mainly stimulate amylase release, and Ca and protein kinase C seem to be equally important in the regulatory mechanism. However, it has recently been found that cholecystokinin and carbachol increased protein tyrosine phosphorylation in addition to serine/threonine phosphorylation and that tyrosine kinase inhibitors significantly inhibited amylase release stimulated by those agonists. These results suggest that tyrosine kinases are involved in the regulation of amylase exocytosis from pancreatic acini. Since little is known concerning the role of tyrosine kinases in parotid acini, we studied the effect of genistein, a tyrosine kinase inhibitor, on amylase release and protein tyrosine phosphorylation. Amylase release stimulated by isoproterenol was dose-dependently inhibited by genistein. Genistein also inhibited the exocytosis evoked by dibutyryl-or 8-chlorophenylthio-cAMP.Daidzein, a negative control agent of genistein, elicited no inhibitory effect. Isoproterenol had dual effects on protein tyrosine phosphorylation ; it increased the phosphorylation of 190-and 210-kDa proteins and decreased that of a 90-kDa one. The phosphorylation was dose-dependently inhibited by genistein but not by daidzein. These results suggest that protein tyrosine phosphorylation plays a role in the process of amylase exocytosis from parotid acinar cells.
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Research Products
(2 results)