Effect of genistein on amylase release and protein tyrosine phosphorylation in parotid acinar cells.
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.
Takuma
T
T
Department of Oral Biochemistry, School of Dentistry, Health Sciences University of Hokkaido, Japan.
Tajima
Y
Y
Ichida
T
T
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
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