Inhibition of histamine release from rat peritoneal mast cells by MY-1250, an active metabolite of Repirinast (MY-5116).
MY-1250, an active metabolite of Repirinast (MY-5116), strongly and dose-dependently inhibited the in vitro histamine release from rat peritoneal mast cells induced by antigen. The IC50 value of MY-1250 for histamine release was in the order of 0.3 microM. Moreover MY-1250 strongly inhibited calcium ion mobilization from the intracellular Ca2+ store. In the presence of 3.6 x 10(-5) M of MY-1250, the initial rise in [Ca2+]i reached a maximum of only 13 nM, and the inhibitory effect was 81% for the initial rise. The IC50 value for this event was 0.25 microM. The inhibitory effect of MY-1250 on the initial rise in [Ca2+]i was closely correlated with that on histamine release.
Takei
M
M
Department of Pharmacology, Tokushima Bunri University, Japan.
Endo
K
K
Takahashi
K
K
D000818:Animals; D002118:Calcium / Q000378:metabolism; D004205:Cromolyn Sodium / Q000494:pharmacology; D006634:Histamine H1 Antagonists / Q000494:pharmacology*; D006636:Histamine Release / Q000187:drug effects*; D008297:Male; D008407:Mast Cells / Q000378:metabolism*; D015363:Quinolones / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D006634:Histamine H1 Antagonists; D015363:Quinolones; C048522:repirinast; C049488:MY 1250; D004205:Cromolyn Sodium; D002118:Calcium