Genistein, an inhibitor of protein tyrosine kinase, is also a competitive antagonist for P1-purinergic (adenosine) receptor in FRTL-5 thyroid cells.
Genistein, a potent inhibitor for protein tyrosine kinase, remarkably inhibited the stimulatory action of N6-(L-2-phenylisopropyl)adenosine (PIA), an A1-adenosine receptor agonist, on thyrotropin (TSH)-induced phospholipase C activation in FRTL-5 thyroid cells. This drug also suppressed both the A1-receptor-mediated inhibition of cAMP accumulation in the cells and binding of [3H]8-cyclopentyl-1,3-dipropylxanthine, a specific antagonist for A1-receptor, to the cell membranes in a competitive manner. Adenosine-induced cAMP accumulation through A2-receptor in pertussis toxin-treated cells was also competitively antagonized by genistein. We conclude that genistein is also a competitive antagonist for P1-purinergic receptors.
Okajima
F
F
Department of Physical Biochemistry, Gunma University, Maebashi, Japan.
Akbar
M
M
Abdul Majid
M
M
Sho
K
K
Tomura
H
H
Kondo
Y
Y
D000243:Adenosine Deaminase / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D000242:Cyclic AMP / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D019833:Genistein; D007295:Inositol Phosphates / Q000378:metabolism; D007529:Isoflavones / Q000494:pharmacology*; D007700:Kinetics; D010660:Phenylisopropyladenosine / Q000494:pharmacology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D058906:Purinergic P1 Receptor Agonists; D058915:Purinergic P1 Receptor Antagonists; D051381:Rats; D013806:Theophylline / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D013961:Thyroid Gland; D013972:Thyrotropin / Q000494:pharmacology*; D010738:Type C Phospholipases / Q000378:metabolism*
D007295:Inositol Phosphates; D007529:Isoflavones; D058906:Purinergic P1 Receptor Agonists; D058915:Purinergic P1 Receptor Antagonists; D010660:Phenylisopropyladenosine; C053907:8-cyclopentyl-1,3-dimethylxanthine; D013972:Thyrotropin; D013806:Theophylline; D019833:Genistein; D000242:Cyclic AMP; D011505:Protein-Tyrosine Kinases; D010738:Type C Phospholipases; D000243:Adenosine Deaminase