Inhibitory effect of adenine nucleotides and anti-allergic drugs on phosphorylation of phosphatidylinositol in rat mast cell granules.
Rat mast cell granules were obtained by sonication of highly purified rat mast cells and isolated in a Percoll gradient. Phosphorylation of endogenous phosphatidylinositol in rat mast cell granules, which is catalyzed by phosphatidylinositol kinase in the granules, was assayed by measuring the incorporation of 32P from [gamma 32P]ATP into phosphatidylinositol 4-phosphate. Lipids were isolated with methanol/chloroform/HCl and were separated by thin-layer chromatography on oxalic acid impregnated silica gel plates. Phosphatidylinositol 4-phosphate areas were identified by staining with iodine, scraped and measured for 32P radioactivity. The phosphorylation reaction was inhibited by 50-500 microM adenosine, ADP and 500 microM AMP in a concentration-dependent manner. Among several anti-allergic drugs investigated. 100-1000 microM theophylline and 10-100 microM azelastine inhibited the phosphorylation reaction, but disodium cromoglycate and ketotifen had little effect.
Kurosawa
M
M
First Department of Internal Medicine, Gunma University School of Medicine, Japan.
Okayama
Y
Y
Kobayashi
S
S
D019870:1-Phosphatidylinositol 4-Kinase; D000227:Adenine Nucleotides / Q000494:pharmacology*; D000241:Adenosine / Q000494:pharmacology; D000244:Adenosine Diphosphate / Q000494:pharmacology; D000249:Adenosine Monophosphate / Q000494:pharmacology; D000818:Animals; D004205:Cromolyn Sodium / Q000494:pharmacology; D003594:Cytoplasmic Granules / Q000378:metabolism*; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D007665:Ketotifen / Q000494:pharmacology; D008407:Mast Cells / Q000378:metabolism* / Q000648:ultrastructure; D010716:Phosphatidylinositols / Q000378:metabolism*; D010766:Phosphorylation; D010770:Phosphotransferases / Q000037:antagonists & inhibitors; D010793:Phthalazines / Q000494:pharmacology; D051381:Rats; D013806:Theophylline / Q000494:pharmacology
D000227:Adenine Nucleotides; D006634:Histamine H1 Antagonists; D010716:Phosphatidylinositols; D010793:Phthalazines; D000249:Adenosine Monophosphate; D000244:Adenosine Diphosphate; D013806:Theophylline; D010770:Phosphotransferases; D019870:1-Phosphatidylinositol 4-Kinase; D000241:Adenosine; D004205:Cromolyn Sodium; D007665:Ketotifen; C020976:azelastine