Stimulation of inositol phosphate production and GTPase activity by compound 48/80 in rat peritoneal mast cells.
Phospholipase C activity, GTPase activity and cytosolic-free calcium concentration in mast cells were stimulated by compound 48/80. Accumulation of inositol phosphates in rat mast cells was stimulated by guanosine 5'-[gamma-thio]-triphosphate. Guanosine 5'-[gamma-thio]triphosphate, however, exhibited no effect upon the purified phospholipase C activity and upon phospholipase C in the mast cell homogenate. The stimulatory effect of compound 48/80 upon phospholipase C activity of intact mast cells was observed to have been well correlated with that on GTPase activity of mast cell homogenate. Compound 48/80 exhibited no effect upon the binding of radioactive guanosine 5'-[gamma-thio]triphosphate to mast cell homogenate. Phospholipase C activity was verified by the above results to become affected by compound 48/80 through guanine nucleotide-binding regulatory protein.
Wu
C Y
CY
Department of Pharmacology, National Yang-Ming Medical College, Taipei, Taiwan, Republic of China.
Chen
C F
CF
Chiang
C F
CF
D000818:Animals; D020558:GTP Phosphohydrolases / Q000378:metabolism*; D016244:Guanosine 5'-O-(3-Thiotriphosphate) / Q000494:pharmacology; D006636:Histamine Release; D007295:Inositol Phosphates / Q000096:biosynthesis*; D008297:Male; D008407:Mast Cells / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D010738:Type C Phospholipases / Q000378:metabolism; D003189:p-Methoxy-N-methylphenethylamine / Q000494:pharmacology*
D007295:Inositol Phosphates; D016244:Guanosine 5'-O-(3-Thiotriphosphate); D003189:p-Methoxy-N-methylphenethylamine; D010738:Type C Phospholipases; D020558:GTP Phosphohydrolases