title: Effect of genistein on amylase release and protein tyrosine phosphorylation in parotid acinar cells.
abstract: We evaluated the role of protein tyrosine phosphorylation in amylase exocytosis from parotid acinar cells by using genistein, a tyrosine kinase inhibitor. 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 that 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.
authors.affiliation: Department of Oral Biochemistry, School of Dentistry, Health Sciences University of Hokkaido, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Takuma
authors.forename: Y
authors.initials: Y
authors.lastname: Tajima
authors.forename: T
authors.initials: T
authors.lastname: Ichida
mesh_terms: D000681:Amylases / Q000378:metabolism*; D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002217:Carbachol / Q000494:pharmacology; D000242:Cyclic AMP / Q000031:analogs & derivatives / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005089:Exocytosis / Q000187:drug effects*; D019833:Genistein; D007529:Isoflavones / Q000494:pharmacology*; D007545:Isoproterenol / Q000494:pharmacology; D010306:Parotid Gland / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D010766:Phosphorylation; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D051381:Rats; D013873:Thionucleotides / Q000494:pharmacology; D014443:Tyrosine / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D007529:Isoflavones; D013873:Thionucleotides; C015929:8-((4-chlorophenyl)thio)cyclic-3',5'-AMP; D014443:Tyrosine; C004742:daidzein; D003994:Bucladesine; D002217:Carbachol; D019833:Genistein; D000242:Cyclic AMP; D011505:Protein-Tyrosine Kinases; D000681:Amylases; D007545:Isoproterenol